FILE - This combination of undated file photos shows Tamerlan Tsarnaev, 26, left, and Dzhokhar Tsarnaev, 19. The CIA added the name of dead Boston Marathon bombing suspect Tamerlan Tsarnaev, to a U.S. government terrorist database 18 months before the deadly explosions, U.S. officials told The Associated Press on Wednesday, April 24, 2013. The CIA's request came about six months after the FBI investigated Tamerlan Tsarnaev, also at the Russian government's request, but the FBI found no ties to terrorism, officials said. Photo: The Lowell Sun & Robin Young  FILE - This combination of undated file photos shows Tamerlan...  Hillary Branyik, of Boston, kneels at the site where the first bomb detonated on April 15 near the finish line of the Boston Marathon on Boylston Street in Boston, Wednesday, April 24, 2013. Traffic was allowed to flow all the way down Boylston Street on Wednesday morning for the first time since two explosions on April 15. Photo: Michael Dwyer  Hillary Branyik, of Boston, kneels at the site where the first bomb...  A makeshift memorial sits at the spot where the first bomb detonated on April 15 near the finish line of the Boston Marathon on Boylston Street in Boston, Wednesday, April 24, 2013. Traffic was allowed to flow all the way down Boylston Street on Wednesday morning for the first time since two explosions on April 15. Photo: Michael Dwyer  A makeshift memorial sits at the spot where the first bomb...  A Revere, Mass. police captain holds his cap while entering a memorial service for fallen Massachusetts Institute of Technology police officer Sean Collier, in Cambridge, Mass., Wednesday, April 24, 2013. Collier was fatally shot on the MIT campus Thursday, April 18, 2013. Authorities allege that the Boston Marathon bombing suspects were responsible. Photo: Steven Senne  A Revere, Mass. police captain holds his cap while entering a...  A police officer takes photos as people arrive to a memorial service for fallen Massachusetts Institute of Technology campus officer Sean Collier at MIT in Cambridge, Mass. Wednesday, April 24, 2013. Collier was fatally shot on the MIT campus Thursday, April 18, 2013. Authorities allege that the Boston Marathon bombing suspects were responsible. Photo: Elise Amendola  A police officer takes photos as people arrive to a memorial...  Antonio DaSilva, of Woburn, Mass., cleans a mark made on the entrance to a building on Boylston Street in Boston, Wednesday, April 24, 2013. Businesses opened and traffic was allowed to flow all the way down Boylston Street on Wednesday morning for the first time since two explosions at the Boston Marathon on April 15. Photo: Michael Dwyer  Antonio DaSilva, of Woburn, Mass., cleans a mark made on the...  Running shoes hang from a barrier at a makeshift memorial in Copley Square on Boylston Street in Boston, Wednesday, April 24, 2013. Traffic was allowed to flow all the way down Boylston Street on Wednesday morning for the first time since two explosions on April 15. Photo: Michael Dwyer  Running shoes hang from a barrier at a makeshift memorial in Copley...  Michelle Littke, of Scituate, Mass., wites on a poster at a makeshift memorial in Copley Square on Boylston Street in Boston, Wednesday, April 24, 2013. Traffic was allowed to flow all the way down Boylston Street on Wednesday morning for the first time since two explosions on April 15. Photo: AP  Michelle Littke, of Scituate, Mass., wites on a poster at a...  An unidentified woman visits the site where the first bomb detonated on April 15 near the finish line of the Boston Marathon on Boylston Street in Boston, Wednesday, April 24, 2013. Traffic was allowed to flow all the way down Boylston Street on Wednesday morning for the first time since two explosions. Photo: Michael Dwyer  An unidentified woman visits the site where the first bomb...  Various items are displayed at a makeshift memorial in Copley Square on Boylston Street in Boston, Wednesday, April 24, 2013. Traffic was allowed to flow all the way down Boylston Street on Wednesday morning for the first time since two explosions on April 15. Photo: Michael Dwyer  Various items are displayed at a makeshift memorial in Copley...  Jill Biden, wife of Vice President Joe Biden, visits the makeshift memorial to the victims of the Boston Marathon bombings, Wednesday, April 24, 0213 on Copley Square Plaza in Boston. BOSTON HERALD OUT, QUINCY OUT; Photo: The Boston Globe, Essdras M. Suarez  Jill Biden, wife of Vice President Joe Biden, visits the makeshift...  Pedestrians pass the spot where the first bomb detonated on Boylston Street near the finish line of the Boston Marathon Wednesday, April 24, 2013, in Boston. Traffic was allowed to flow all the way down Boylston Street on Wednesday morning for the first time since two explosions killed 3 people and injured many on April 15. Photo: Michael Dwyer  Pedestrians pass the spot where the first bomb detonated on...  Vocal Point, a group from the University of Missouri St. Louis, sings at a makeshift memorial in Copley Square on Boylston Street in Boston, Wednesday, April 24, 2013. Traffic was allowed to flow all the way down Boylston Street on Wednesday morning for the first time since two explosions on April 15. Photo: Michael Dwyer  Vocal Point, a group from the University of Missouri St. Louis,...  Robert Rogers, left, puts his hand on his step brother, Andrew Collier, after delivering the eulogy at a memorial service for slain Massachusetts Institute of Technology campus officer, Sean Collier, at MIT in Cambridge, Mass. Wednesday, April 24, 2013. Sean Collier was fatally shot on the MIT campus Thursday, April 18, 2013. Authorities allege that the Boston Marathon bombing suspects were responsible. Photo: AP  Robert Rogers, left, puts his hand on his step brother, Andrew...  Employess greet people outside of Trader Joe's on Boylston Street in Boston, Wednesday, April 24, 2013, as businesses opened and traffic was allowed to flow all the way down Boylston Street for the first time since two explosions at the Boston Marathon on April 15. Photo: Michael Dwyer  Employess greet people outside of Trader Joe's on Boylston Street...  Employess greet people outside of Trader Joe's on Boylston Street in Boston, Wednesday, April 24, 2013, as businesses opened and traffic was allowed to flow all the way down Boylston Street for the first time since two explosions at the Boston Marathon on April 15. Photo: Michael Dwyer  Employess greet people outside of Trader Joe's on Boylston Street...  A police officer and a woman react to news of the arrest of one of the Boston Marathon bombing suspects, Friday, April 19, 2013, in Boston. Boston Marathon bombing suspect Dzhokhar Tsarnaev was captured in Watertown, Mass. The 19-year-old college student wanted in the bombings was taken into custody Friday evening after a manhunt that left the city virtually paralyzed and his older brother and accomplice dead. (AP Photo/Julio Cortez) Photo: Julio Cortez, Wire  A police officer and a woman react to news of the arrest of one of...  State Police Col. Timothy Alben, accompanied by Massachusetts Governor Deval Patrick, speaks during a news conference, after the arrest of a suspect of the Boston Marathon bombings in Watertown, Mass., Friday, April 19, 2013. A 19-year-old college student wanted in the Boston Marathon bombings was taken into custody Friday evening after a manhunt that left the city virtually paralyzed and his older brother and accomplice dead. (AP Photo/Matt Rourke)(AP Photo/Matt Rourke) Photo: Matt Rourke, Wire  State Police Col. Timothy Alben, accompanied by Massachusetts...  WASHINGTON, DC - APRIL 19: U.S. President Barack Obama speaks from the White House about the capture of Dzhokhar A. Tsarnaev on April 19, 2013 in Washington, DC. A manhunt for a suspect in the Boston Marathon bombing, Dzhokhar A. Tsarnaev, 19, ended this evening with his capture on a boat parked on a residential property in Watertown, Massachusetts. His brother Tamerlan Tsarnaev, 26, the other suspect, was shot and killed by police early this morning after a car chase and shootout with police. The two men are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170. (Photo by Win McNamee/Getty Images) Photo: Win McNamee, Wire  WASHINGTON, DC - APRIL 19: U.S. President Barack Obama speaks from...  WATERTOWN, MA - APRIL 19: Alcohol, Tobacco and Firearm police relax after enjoying a meal following the apprehension earlier of the second suspect in the Boston Marathon bombing on April 19, 2013 in Watertown, Massachusetts. A manhunt for a suspect in the Boston Marathon bombing, Dzhokhar A. Tsarnaev, 19, ended this evening with his capture on a boat parked on a residential property in Watertown, Massachusetts. His brother Tamerlan Tsarnaev, 26, the other suspect, was shot and killed by police early this morning after a car chase and shootout with police. The two men are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170. (Photo by Kevork Djansezian/Getty Images) Photo: Kevork Djansezian, Wire  WATERTOWN, MA - APRIL 19: Alcohol, Tobacco and Firearm police...  BOSTON - APRIL 19: Police motorcade with officers from, Boston, Canton, Hanover, Duxbury, Randolph, and Dedham, leave Beth Israel Deaconess Medical Center West Campus. After an intense manhunt and two-hour standoff in Watertown, law enforcement took a person into custody believed to be related to the Boston Marathon bombings. (Photo by Matthew J. Lee/The Boston Globe via Getty Images) Photo: Boston Globe, Wire  BOSTON - APRIL 19: Police motorcade with officers from, Boston,...  WATERTOWN, MA - APRIL 19: Alcohol, Tobacco and Firearm police relax with a meal following the apprehension earlier of the second suspect in the Boston Marathon bombing on April 19, 2013 in Watertown, Massachusetts. A manhunt for a suspect in the Boston Marathon bombing, Dzhokhar A. Tsarnaev, 19, ended this evening with his capture on a boat parked on a residential property in Watertown, Massachusetts. His brother Tamerlan Tsarnaev, 26, the other suspect, was shot and killed by police early this morning after a car chase and shootout with police. The two men are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170. (Photo by Kevork Djansezian/Getty Images) Photo: Kevork Djansezian, Wire  WATERTOWN, MA - APRIL 19: Alcohol, Tobacco and Firearm police...  WATERTOWN, MA - APRIL 19: People celebrate on Mt. Auburn Street. After an intense manhunt and two-hour standoff in Watertown, law enforcement took a person into custody believed to be related to the Boston Marathon bombings. (Photo by Jonathan Wiggs/The Boston Globe via Getty Images) Photo: Boston Globe, Wire  WATERTOWN, MA - APRIL 19: People celebrate on Mt. Auburn Street....  BOSTON - APRIL 19: An estimated 200 people pour onto Hemingway Street in the Fenway neighborhood to celebrate after the announcement earlier of the capture of the second Boston Martathon bombing suspect celebrate April 19, 2013 in Boston, Massachusetts. A manhunt for Dzhokhar A. Tsarnaev, 19, ended this evening with his capture on a boat parked on a residential property in Watertown, Massachusetts. His brother Tamerlan Tsarnaev, 26, the other suspect, was shot and killed by police early this morning after a car chase and shootout with police. The bombing killed three people and wounded at least 170. (Photo by Kayana Szymczak/Getty Images) Photo: Kayana Szymczak, Wire  BOSTON - APRIL 19: An estimated 200 people pour onto Hemingway...  BOSTON - APRIL 19: A few of the estimated 200 people who poured onto Hemingway Street in the Fenway neighborhood to celebrate after the announcement earlier of the capture of the second Boston Martathon bombing suspect celebrate April 19, 2013 in Boston, Massachusetts. A manhunt for Dzhokhar A. Tsarnaev, 19, ended this evening with his capture on a boat parked on a residential property in Watertown, Massachusetts. His brother Tamerlan Tsarnaev, 26, the other suspect, was shot and killed by police early this morning after a car chase and shootout with police. The bombing killed three people and wounded at least 170. (Photo by Kayana Szymczak/Getty Images) Photo: Kayana Szymczak, Wire  BOSTON - APRIL 19: A few of the estimated 200 people who poured...  WATERTOWN, MA - APRIL 19: SWAT team members exit Franklin Street in Watertown with visible relief on their faces. After an intense manhunt and two-hour standoff in Watertown, law enforcement took a person into custody believed to be related to the Boston Marathon bombings. (Photo by Barry Chin/The Boston Globe via Getty Images) Photo: Boston Globe, Wire  WATERTOWN, MA - APRIL 19: SWAT team members exit Franklin Street in...  WATERTOWN, MA - APRIL 19: On Arsenal Street, Louise Hunter and others cheer on police on leaving the scene. After an intense manhunt and two-hour standoff in Watertown, law enforcement took a person into custody believed to be related to the Boston Marathon bombings. (Photo by Bill Greene/The Boston Globe via Getty Images) Photo: Boston Globe, Wire  WATERTOWN, MA - APRIL 19: On Arsenal Street, Louise Hunter and...  BOSTON - APRIL 19: After the second suspect was captured, people came to the barricades at the corner of Boylston and Hereford Streets near the Marathon Finish line to celebrate and reflect. A couple looks at a device as the woman carries an American flag. (Photo by Jim Davis/The Boston Globe via Getty Images) Photo: Boston Globe, Wire  BOSTON - APRIL 19: After the second suspect was captured, people...  Joseph Eli Libby, 20, of Boston, carries a flag near a makeshift memorial on Boylston Street, near the finish line of the Boston Marathon, Friday, April 19, 2013, in Boston. Boston Marathon bombing suspect Dzhokhar Tsarnaev was captured in Watertown, Mass. The 19-year-old college student wanted in the bombings was taken into custody Friday evening after a manhunt that left the city virtually paralyzed and his older brother and accomplice dead. (AP Photo/Julio Cortez) Photo: Julio Cortez, Wire  Joseph Eli Libby, 20, of Boston, carries a flag near a makeshift...  Mimi de Quesada, of Watertown, Mass., reacts while standing by her home in the wake of the sound of shots fired in Watertown, Mass., Friday, April 19, 2013, as a massive search continued for one of two suspects in the Boston Marathon bombings. De Quesada said she had just come out to enjoy the day when the shots rang out about two blocks form her home. A second suspect died in the early morning hours after an encounter with law enforcement. (AP Photo/Craig Ruttle) Photo: Wire  Mimi de Quesada, of Watertown, Mass., reacts while standing by her...  Many different law enforcement agencies descend on an area around Franklin Street on April 19, 2013 in Watertown, Massachusetts. After a car chase and shootout with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170.  Many different law enforcement agencies descend on an area around...  Residents embrace prior to the capture of the second of two suspects wanted in the Boston Marathon bombings April 19, 2013 in Watertown, Massachusetts. Thousands of heavily armed police staged an intense manhunt for a Chechen teenager suspected in the Boston marathon bombings with his brother, who was killed in a shootout. Dzhokhar Tsarnaev, 19, defied the massive force after his 26-year-old brother Tamerlan was shot and suffered critical injuries from explosives believed to have been strapped to his body. AFP PHOTO / TIMOTHY A. CLARY (Photo credit should read TIMOTHY A. CLARY/AFP/Getty Images) Photo: TIMOTHY A. CLARY, Wire  Residents embrace prior to the capture of the second of two...  Residents await the capture of the second of two suspects wanted in the Boston Marathon bombings April 19, 2013 in Watertown, Massachusetts. Thousands of heavily armed police staged an intense manhunt for a Chechen teenager suspected in the Boston marathon bombings with his brother, who was killed in a shootout. Dzhokhar Tsarnaev, 19, defied the massive force after his 26-year-old brother Tamerlan was shot and suffered critical injuries from explosives believed to have been strapped to his body. AFP PHOTO / TIMOTHY A. CLARY (Photo credit should read TIMOTHY A. CLARY/AFP/Getty Images) Photo: TIMOTHY A. CLARY, Wire  Residents await the capture of the second of two suspects wanted...  WATERTOWN, MA - APRIL 19: Spectators clap and cheer while law enforcement members leave the scene near Franklin Street on April 19, 2013 in Watertown, Massachusetts. A manhunt for a suspect in the Boston Marathon bombing, Dzhokhar A. Tsarnaev, 19, ended this evening with his capture on a boat parked on a residential property in Watertown, Massachusetts. His brother Tamerlan Tsarnaev, 26, the other suspect, was shot and killed by police early this morning after a car chase and shootout with police. The two men are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170. (Photo by Jared Wickerham/Getty Images) Photo: Jared Wickerham, Wire  WATERTOWN, MA - APRIL 19: Spectators clap and cheer while law...  WATERTOWN, MA - APRIL 19: Spectators clap and cheer while law enforcement members leave the scene near Franklin Street on April 19, 2013 in Watertown, Massachusetts. A manhunt for a suspect in the Boston Marathon bombing, Dzhokhar A. Tsarnaev, 19, ended this evening with his capture on a boat parked on a residential property in Watertown, Massachusetts. His brother Tamerlan Tsarnaev, 26, the other suspect, was shot and killed by police early this morning after a car chase and shootout with police. The two men are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170. (Photo by Jared Wickerham/Getty Images) Photo: Jared Wickerham, Wire  WATERTOWN, MA - APRIL 19: Spectators clap and cheer while law...  WATERTOWN, MA - APRIL 19: Two police officers laugh while securing the area around Franklin Street on April 19, 2013 in Watertown, Massachusetts. A manhunt for a suspect in the Boston Marathon bombing, Dzhokhar A. Tsarnaev, 19, ended this evening with his capture on a boat parked on a residential property in Watertown, Massachusetts. His brother Tamerlan Tsarnaev, 26, the other suspect, was shot and killed by police early this morning after a car chase and shootout with police. The two men are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170. (Photo by Jared Wickerham/Getty Images) Photo: Jared Wickerham, Wire  WATERTOWN, MA - APRIL 19: Two police officers laugh while securing...  WATERTOWN, MA - APRIL 19: Women cheer police as they exit Franklin Street after 19-year-old bombing suspect Dzhokhar A. Tsarnaev was apprehended on April 19, 2013 in Watertown, Massachusetts. A manhunt for Boston Marathon bombing suspect Tsarnaev ended this evening with his capture on a boat parked on a residential property in Watertown, Massachusetts. His brother Tamerlan Tsarnaev, 26, the other suspect, was shot and killed by police early this morning after a car chase and shootout with police. The two men are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170.(Photo by Spencer Platt/Getty Images) Photo: Spencer Platt, Wire  WATERTOWN, MA - APRIL 19: Women cheer police as they exit Franklin...  WATERTOWN, MA - APRIL 19: A SWAT team member is followed by reporters and a celebrating crowd after the successful operation to capture 19-year-old bombing suspect Dzhokhar A. Tsarnaev on April 19, 2013 in Watertown, Massachusetts. A manhunt for a suspect in the Boston Marathon bombing, Dzhokhar A. Tsarnaev, 19, ended this evening with his capture on a boat parked on a residential property in Watertown, Massachusetts. His brother Tamerlan Tsarnaev, 26, the other suspect, was shot and killed by police early this morning after a car chase and shootout with police. The two men are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170. (Photo by Mario Tama/Getty Images) Photo: Mario Tama, Wire  WATERTOWN, MA - APRIL 19: A SWAT team member is followed by...  WATERTOWN, MA - APRIL 19: Members of a police S.W.A.T. team exit Franklin Street moments after 19-year-old bombing suspect Dzhokhar A. Tsarnaev was apprehended on April 19, 2013 in Watertown, Massachusetts. A manhunt for Boston Marathon bombing suspect Tsarnaev ended this evening with his capture on a boat parked on a residential property in Watertown, Massachusetts. His brother Tamerlan Tsarnaev, 26, the other suspect, was shot and killed by police early this morning after a car chase and shootout with police. The two men are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170.(Photo by Spencer Platt/Getty Images) Photo: Spencer Platt, Wire  WATERTOWN, MA - APRIL 19: Members of a police S.W.A.T. team exit...  This still frame from video shows Boston Marathon bombing suspect Dzhokhar Tsarnaev visible through an ambulance after he was captured in Watertown, Mass., Friday, April 19, 2013. A 19-year-old college student wanted in the Boston Marathon bombings was taken into custody Friday evening after a manhunt that left the city virtually paralyzed and his older brother and accomplice dead. (AP Photo/Robert Ray) Photo: Robert Ray, Wire  This still frame from video shows Boston Marathon bombing suspect...  Many different law enforcement agencies descend on an area around Franklin Street on April 19, 2013 in Watertown, Massachusetts. After a car chase and shootout with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170. Photo: Jared Wickerham, Getty Images  Many different law enforcement agencies descend on an area around...  Police converge near the scene where it was believed 19-year-old bombing suspect Dzhokhar A. Tsarnaev is in hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly of Chechen origin, are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. Photo: Spencer Platt, Getty Images  Police converge near the scene where it was believed 19-year-old...  Many different law enforcement agencies descend on an area around Franklin Street on April 19, 2013 in Watertown, Massachusetts. After a car chase and shootout with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170. Photo: Jared Wickerham, Getty Images  Many different law enforcement agencies descend on an area around...  WATERTOWN, MA - APRIL 19: Residents flee from an area where a suspect is hiding on Franklin St., on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Photo by Darren McCollester/Getty Images) Photo: Darren McCollester, Wire  WATERTOWN, MA - APRIL 19: Residents flee from an area where a...  WATERTOWN, MA - APRIL 19: An officer carries a child away from an area where a suspect is hiding on Franklin St., on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Photo by Darren McCollester/Getty Images) Photo: Darren McCollester, Wire  WATERTOWN, MA - APRIL 19: An officer carries a child away from an...  Law enforcement evacuate people near to where a suspect is hiding on Franklin St., April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. Photo: Darren McCollester, Getty Images  Law enforcement evacuate people near to where a suspect is hiding...  Members of a police S.W.A.T. team run to the area where it was believed 19-year-old bombing suspect Dzhokhar A. Tsarnaev is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police last night, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly of Chechen of origin, are suspects in the bombings at the Boston Marathon on April 15 that killed three people and wounded at least 170. Photo: Spencer Platt, Getty Images  Members of a police S.W.A.T. team run to the area where it was...  Law enforcement evacuate people away from an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. Photo: Darren McCollester, Getty Images  Law enforcement evacuate people away from an area reportedly where...  Family members who fled the scene where it was believed 19-year-old bombing suspect Dzhokhar A. Tsarnaev is in hiding are comforted on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly of Chechen origin, are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. Photo: Spencer Platt, Getty Images  Family members who fled the scene where it was believed 19-year-old...  Law enforcement approach an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. Photo: Darren McCollester, Getty Images  Law enforcement approach an area reportedly where a suspect is...  Law enforcement approach an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. Photo: Darren McCollester, Getty Images  Law enforcement approach an area reportedly where a suspect is...  Resident Rosie Meyer, who said she heard gunshots, reacts while watching police respond on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly Chechen of origin, are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. Photo: Mario Tama, Getty Images  Resident Rosie Meyer, who said she heard gunshots, reacts while...  Law enforcement approach an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. Photo: Darren McCollester, Getty Images  Law enforcement approach an area reportedly where a suspect is...  WATERTOWN, MA - APRIL 19: Massachusetts State Police Colonel Timothy Alben addresses the media April 19, 2013 in Watertown, Massachusetts. The lockdown of Watertown has been lifted after last nights shootout between police and the two Boston Marathon bombing suspects. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Photo by Darren McCollester/Getty Images) Photo: Darren McCollester, Wire  WATERTOWN, MA - APRIL 19: Massachusetts State Police Colonel...  A news reporter waits for her cue as police guard the apartment building where the sister of the Boston marathon bombing suspects is believed to live, Friday, April 19, 2013, in West New York, N.J. Federal investigators had removed items from the house earlier in the day, although there is no indication that the sister was involved in the bombing. (AP Photo/John Minchillo) Photo: Wire  A news reporter waits for her cue as police guard the apartment...  Members of a police S.W.A.T. team search through a neighborhood in Watertown as they search for 19-year-old bombing suspect Dzhokhar A. Tsarnaev on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. Photo: Spencer Platt, Getty Images  Members of a police S.W.A.T. team search through a neighborhood in...  Members of a police SWAT team conduct a door-to-door search for 19-year-old Boston Marathon bombing suspect Dzhokhar A. Tsarnaev on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. Photo: Spencer Platt, Getty Images  Members of a police SWAT team conduct a door-to-door search for...  U.S. military helicopters fly over mobile television dishes during the search for 19-year-old Boston Marathon bombing suspect Dzhokhar A. Tsarnaev on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old Dzhokhar A. Tsarnaev. The two men are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. Photo: Mario Tama, Getty Images  U.S. military helicopters fly over mobile television dishes during...  A police SWAT team search houses for the second of two suspects wanted in the Boston Marathon bombings takes place April 19, 2013 in Watertown, Massachusetts. Thousands of heavily armed police staged an intense manhunt Friday for a Chechen teenager suspected in the Boston marathon bombings with his brother, who was killed in a shootout. Dzhokhar Tsarnaev, 19, defied the massive force after his 26-year-old brother Tamerlan was shot and suffered critical injuries from explosives believed to have been strapped to his body. AFP PHOTO / TIMOTHY A. CLARY Photo: Getty Images  A police SWAT team search houses for the second of two suspects...  This photo released Friday, April 19, 2013 by the Federal Bureau of Investigation shows a suspect that officials identified as Dzhokhar Tsarnaev, being sought by police in the Boston Marathon bombings Monday. Photo: Federal Bureau Of Investigation  This photo released Friday, April 19, 2013 by the Federal Bureau of...  In this Feb. 17, 2010, photo, Tamerlan Tsarnaev, left, accepts the trophy for winning the 2010 New England Golden Gloves Championship from Dr. Joseph Downes, right, in Lowell, Mass. Tsarnaev, 26, who had been known to the FBI as Suspect No. 1 in the Boston Marathon Explosions and was seen in surveillance footage in a black baseball cap, was killed overnight on Friday, April 19, 2013, officials said. (AP Photo/The Lowell Sun, Julia Malakie)  In this Feb. 17, 2010, photo, Tamerlan Tsarnaev, left, accepts the...  Police action at 17 Willow Avenue during the ongoing manhunt for a suspect in the terrorist bombing of the 117th Boston Marathon earlier this week. Watertown is on lockdown following a chase and shootout in the area last night. Photo: Boston Globe, Getty Images  Police action at 17 Willow Avenue during the ongoing manhunt for a...  SWAT search on Nichols Avenue at the corner of Dexter during the ongoing manhunt for a suspect in the terrorist bombing of the 117th Boston Marathon earlier this week. Watertown is on lockdown following a chase and shootout in the area last night. Photo: Boston Globe, Getty Images  SWAT search on Nichols Avenue at the corner of Dexter during the...  WATERTOWN, MA - APRIL 19: SWAT teams moved into position at the intersection of Nichols Avenue and Melendy Avenue in Watertown while searching for one of the two marathon bombing suspects. Photo: Boston Globe, Getty Images  WATERTOWN, MA - APRIL 19: SWAT teams moved into position at the...  State Police officers stop a car at the intersection of Carver Road and Belmont Street in Watertown while searching for one of the two suspects in the terrorist bombing of the 117th Boston Marathon earlier this week. Photo: Boston Globe, Getty Images  State Police officers stop a car at the intersection of Carver Road...  Tamerlan and Dzhokhar Tsarnaev's aunt Maret Tsarnaeva spoke to Toronto media in the lobby of her Etobicoke apartment building April 19, 1013. Dzhokhar Tsarnaev is the suspect at large wanted in connection with the Boston bombings. Tamerlan was killed by Boston police in a shootout. Photo: Lucas Oleniuk, Getty Images  Tamerlan and Dzhokhar Tsarnaev's aunt Maret Tsarnaeva spoke to...  Massachusetts Governor Deval Patrick (at microphone) speaks to the media with Boston Mayor Thomas Menino (L, in wheelchair), Boston Police Commissioner Ed Davis (L, behind Menino) and Watertown Chief of Police Edward P. Deveau (R, behind Patrick) at the Watertown Mall as a search for the second of two suspects wanted in the Boston Marathon bombings takes place April 19, 2013 in Watertown, Massachusetts. Photo: STAN HONDA, Getty Images  Massachusetts Governor Deval Patrick (at microphone) speaks to the...  SWAT teams searched homes along Winsor Avenue in Watertown while searching for one of the two suspects in the terrorist bombing of the 117th Boston Marathon earlier this week. Photo: Boston Globe, Getty Images  SWAT teams searched homes along Winsor Avenue in Watertown while...  SWAT teams searched homes along Winsor Avenue in Watertown while searching for one of the two suspects in the terrorist bombing of the 117th Boston Marathon earlier this week. Photo: Boston Globe, Getty Images  SWAT teams searched homes along Winsor Avenue in Watertown while...  A National Guard helicopter prepares to land behind the Watertown Mall as a search for the second of two suspects wanted in the Boston Marathon bombings takes place April 19, 2013 in Watertown, Massachusetts. Thousands of heavily armed police staged an intense manhunt Friday for a Chechen teenager suspected in the Boston marathon bombings with his brother, who was killed in a shootout. Dzhokhar Tsarnaev, 19, defied the massive force after his 26-year-old brother Tamerlan was shot and suffered critical injuries from explosives believed to have been strapped to his body. AFP PHOTO/Stan HONDA Photo: STAN HONDA, Getty Images  A National Guard helicopter prepares to land behind the Watertown...  A barefooted woman runs for cover as police surround a home while searching for a suspect in the Boston Marathon bombings in Watertown, Mass., Friday, April 19, 2013. Two suspects in the Boston Marathon bombing killed an MIT police officer, injured a transit officer in a firefight and threw explosive devices at police during a getaway attempt in a long night of violence that left one of them dead and another still at large Friday, authorities said as the manhunt intensified for a young man described as a dangerous terrorist. (AP Photo/Charles Krupa) Photo: Associated Press  A barefooted woman runs for cover as police surround a home while...  Members of a SWAT team search for 19-year-old bombing suspect Dzhokhar A. Tsarnaev on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly Chechen of origin, are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. Photo: Mario Tama, Getty Images  Members of a SWAT team search for 19-year-old bombing suspect...  Ruslan Tsarni, the uncle of the Boston Marathon bombing suspect, speaks with the media outside his home in Montgomery Village in Md. Friday, April, 19, 2013. Tsarni urged his nephew to turn himself in. Photo: Associated Press  Ruslan Tsarni, the uncle of the Boston Marathon bombing suspect,...  SWAT teams searched homes along Winsor Avenue in Watertown while searching for one of the two suspects in the terrorist bombing of the 117th Boston Marathon earlier this week. Photo: Boston Globe, Getty Images  SWAT teams searched homes along Winsor Avenue in Watertown while...  A member of the Cambridge police bomb squad, right, deploys a robot on Norfolk Street during a search for searching a suspect in the Boston Marathon bombings in Cambridge, Mass., Friday, April 19, 2013. Two suspects in the Boston Marathon bombing killed an MIT police officer, injured a transit officer in a firefight and threw explosive devices at police during a getaway attempt in a long night of violence that left one of them dead and another still at large Friday, authorities said as the manhunt intensified for a young man described as a dangerous terrorist. Photo: Associated Press  A member of the Cambridge police bomb squad, right, deploys a robot...  A police officer evacuates a shoeless man holding a child as members of law enforcement conduct a search for a suspect in the Boston Marathon bombings, Friday, April 19, 2013, in Watertown, Mass. The two suspects in the Boston Marathon bombing killed an MIT police officer and hurled explosives at police in a car chase and gun battle overnight that left one of them dead and his brother on the loose, authorities said Friday as thousands of officers swarmed the streets in a manhunt that all but paralyzed the Boston area. Photo: Associated Press  A police officer evacuates a shoeless man holding a child as...  SWAT teams moved into position at the intersection of Nichols Avenue and Melendy Avenue in Watertown while searching for one of the two marathon bombing suspects. Photo: Boston Globe, Getty Images  SWAT teams moved into position at the intersection of Nichols...  SWAT teams moved into position at the intersection of Nichols Avenue and Melendy Avenue in Watertown while searching for one of the two marathon bombing suspects. Photo: Boston Globe, Getty Images  SWAT teams moved into position at the intersection of Nichols...  FBI and local law enforcement personnel continue their search for a suspect in the Boston Marathon bombings on Norfolk Street in Cambridge, Mass., Friday, April 19, 2013. Two suspects in the Boston Marathon bombing killed an MIT police officer, injured a transit officer in a firefight and threw explosive devices at police during a getaway attempt in a long night of violence that left one of them dead and another still at large Friday, authorities said as the manhunt intensified for a young man described as a dangerous terrorist. Photo: Michael Dwyer, Getty Images  FBI and local law enforcement personnel continue their search for a...  This undated photo provided by the Middlesex District Attorney's Office shows Massachusetts Institute of Technology Police Officer Sean Collier, 26, of Somerville, Mass., who was shot to death Thursday, April 18, 2013 on the school campus in Cambridge, Mass. Authorities said surveillance tape recorded late Thursday showed one of the Boston Marathon bombing suspects during a robbery of a nearby convenience store before Collier was shot to death while responding to a report of a disturbance. Photo: Uncredited, Getty Images  This undated photo provided by the Middlesex District Attorney's...  A resident evacuates as police go door-to-door on Norfolk Street in search of a suspect in the Boston Marathon bombings in Cambridge, Mass., Friday, April 19, 2013. Two suspects in the Boston Marathon bombing killed an MIT police officer, injured a transit officer in a firefight and threw explosive devices at police during a getaway attempt in a long night of violence that left one of them dead and another still at large Friday, authorities said as the manhunt intensified for a young man described as a dangerous terrorist. Photo: Michael Dwyer, Getty Images  A resident evacuates as police go door-to-door on Norfolk Street in...  State Police search for second suspect on Mount Auburn Street near Watertown Square. A manhunt is underway for a suspect in the terrorist bombing of the 117th Boston Marathon earlier this week. Photo: Boston Globe, Getty Images  State Police search for second suspect on Mount Auburn Street near...  Federal agents descend on the home of a suspect-at-large in the Boston Marathon bombing and nearby Watertown shooting, on Norfolk Street April 19, 2013 in Cambridge, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Darren McCollester, Getty Images  Federal agents descend on the home of a suspect-at-large in the...  The Boston area is under lockdown as as a manhunt is underway for a suspect in the terrorist bombing of the 117th Boston Marathon earlier this week. The Mass. Avenue bridge has only a few pedestrians crossing. Photo: Boston Globe, Getty Images  The Boston area is under lockdown as as a manhunt is underway for a...  This undated photo provided by the vkontakte website shows Dzhokhar Tsarnaev. Dzhokhar Tsarnaev has been on the run, described as "armed and dangerous" and suspected of the Boston Marathon bombing. His brother, Tamerlan, was killed during a violent police chase. The two ethnic Chechen brothers came from Dagestan, a Russian republic bordering the province of Chechnya. Photo: Uncredited, Getty Images  This undated photo provided by the vkontakte website shows Dzhokhar...  This Monday, April 15, 2013, shows a man who was dubbed Suspect No. 2 in the Boston Marathon bombings by law enforcement, in the upper center of the frame, wearing a white baseball cap, walking away from the scene of the explosions. The FBI identified him as 19-year-old college student Dzhokhar Tsarnaev, who along with his brother Tamerlan, 26, previously known as Suspect No. 1, killed an MIT police officer, severely wounded another lawman and hurled explosives at police in a car chase and gun battle during a night of violence, early Friday, April 19, 2013. Tamerlan Tsarnaev was killed overnight, officials said, while his brother Dzhokhar remains at large. Photo: Associated Press  This Monday, April 15, 2013, shows a man who was dubbed Suspect No....  Police in tactical gear arrive on an armored police vehicle as they surround an apartment building while looking for a suspect in the Boston Marathon bombings in Watertown, Mass., Friday, April 19, 2013. The bombs that blew up seconds apart near the finish line of the Boston Marathon left the streets spattered with blood and glass, and gaping questions of who chose to attack and why. Photo: Charles Krupa  Police in tactical gear arrive on an armored police vehicle as they...  A Department of Homeland Security officer, right, prepares to enter an apartment building while looking for a suspect in the Boston Marathon bombings in Watertown, Mass., Friday, April 19, 2013. The bombs that blew up seconds apart near the finish line of the Boston Marathon left the streets spattered with blood and glass, and gaping questions of who chose to attack and why. Photo: Charles Krupa  A Department of Homeland Security officer, right, prepares to enter...  WATERTOWN, MA - APRIL 19: A Massachusetts State Police officer checks the bag of a cyclist during heightened security on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Mario Tama, Getty Images  WATERTOWN, MA - APRIL 19: A Massachusetts State Police officer...  WATERTOWN, MA - APRIL 19: SWAT team members search for one remaining suspect at a residential building as a man looks out from a window on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Mario Tama, Getty Images  WATERTOWN, MA - APRIL 19: SWAT team members search for one...  A dog sniffs equipment before Massachusetts Governor Deval Patrick spoke to the media at a shopping mall on the perimeter of a locked down area as a search for the second of two suspects wanted in the Boston Marathon bombings takes place on April 19, 2013 in Watertown, Massachusetts. AFP PHOTO/Stan HONDA Photo: STAN HONDA, Getty Images  A dog sniffs equipment before Massachusetts Governor Deval Patrick...  WATERTOWN, MA - APRIL 19: Members of the FBI, State Police, Boston Police, Cambridge Police, and other law enforcement agencies, put up police tape securing a perimeter in front of a woman being questioned by the FBI on April 19, 2013 near the home of suspect #2 on Norfolk Street in Cambridge, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Jared Wickerham, Getty Images  WATERTOWN, MA - APRIL 19: Members of the FBI, State Police, Boston...  WATERTOWN, MA - APRIL 19: A woman reacts while being questioned by the FBI and other law enforcement agencies on April 19, 2013 near the home of suspect #2 on Norfolk Street in Cambridge, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Jared Wickerham, Getty Images  WATERTOWN, MA - APRIL 19: A woman reacts while being questioned by...  WATERTOWN, MA - APRIL 19: Residents of an apartment building watch as members of the FBI, State Police, Boston Police, Cambridge Police, and other law enforcement agencies, survey the perimeter on April 19, 2013 near the home of suspect #2 on Norfolk Street in Cambridge, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Jared Wickerham, Getty Images  WATERTOWN, MA - APRIL 19: Residents of an apartment building watch...  Katia Costa looks out her window at all the police activity below on the street at Nichols Avenue during the ongoing manhunt for a suspect in the terrorist bombing of the 117th Boston Marathon earlier this week. Watertown is on lockdown following a chase and shootout in the area last night. Photo: Boston Globe, Getty Images  Katia Costa looks out her window at all the police activity below...  WATERTOWN, MA - APRIL 19: Members of the FBI, State Police, Boston Police, Cambridge Police, and other law enforcement agencies, survey the perimeter on April 19, 2013 near the home of suspect #2 on Norfolk Street in Cambridge, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Jared Wickerham, Getty Images  WATERTOWN, MA - APRIL 19: Members of the FBI, State Police, Boston...  WATERTOWN, MA - APRIL 19: A woman reacts while being questioned by the Cambridge Police and other law enforcement agencies on April 19, 2013 near the home of suspect #2 on Norfolk Street in Cambridge, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Jared Wickerham, Getty Images  WATERTOWN, MA - APRIL 19: A woman reacts while being questioned by...  Police work a crime scene Friday, April 19, 2013, in Watertown, Mass. A tense night of police activity that left a university officer dead on campus just days after the Boston Marathon bombings and amid a hunt for two suspects caused officers to converge on a neighborhood outside Boston, where residents heard gunfire and explosions. Photo: AP  Police work a crime scene Friday, April 19, 2013, in Watertown,...  Police officers walk near a crime scene Friday, April 19, 2013, in Watertown, Mass. A tense night of police activity that left a university officer dead on campus just days after the Boston Marathon bombings and amid a hunt for two suspects caused officers to converge on a neighborhood outside Boston, where residents heard gunfire and explosions. Photo: AP  Police officers walk near a crime scene Friday, April 19, 2013, in...  WATERTOWN, MA - APRIL 19: Police descend on School and Walnut Street chasing possible suspects on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Darren McCollester, Getty Images  WATERTOWN, MA - APRIL 19: Police descend on School and Walnut...  WATERTOWN, MA - APRIL 19: Police descend on School and Walnut Street chasing possible suspects on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Darren McCollester, Getty Images  WATERTOWN, MA - APRIL 19: Police descend on School and Walnut...  WATERTOWN, MA - APRIL 19: A police officer with gun drawn and flashlight searches for a suspect on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Mario Tama, Getty Images  WATERTOWN, MA - APRIL 19: A police officer with gun drawn and...  A Boston police officer mans a closed off neighborhood as a search for the second of two suspects wanted in the Boston Marathon bombings takes place April 19, 2013 in Watertown, Massachusetts. Police killed one of the suspected Boston marathon bombing suspects in a shootout early today and pursued a chaotic deadly street-to-street manhunt for his accomplice, officials said. AFP PHOTO/Stan HONDA Photo: STAN HONDA, Getty Images  A Boston police officer mans a closed off neighborhood as a search...  A Boston police officer allows police vehicles out of a closed area as a search for the second of two suspects wanted in the Boston Marathon bombings takes place April 19, 2013 in Watertown, Massachusetts. Police killed one of the suspected Boston marathon bombing suspects in a shootout early today and pursued a chaotic deadly street-to-street manhunt for his accomplice, officials said. AFP PHOTO/Stan HONDA Photo: STAN HONDA, Getty Images  A Boston police officer allows police vehicles out of a closed area...  A Boston police officer allows a police vehicle into a closed area as a search for the second of two suspects wanted in the Boston Marathon bombings takes place April 19, 2013 in Watertown, Massachusetts. Police killed one of the suspected Boston marathon bombing suspects in a shootout early today and pursued a chaotic deadly street-to-street manhunt for his accomplice, officials said. AFP PHOTO/Stan HONDA Photo: STAN HONDA, Getty Images  A Boston police officer allows a police vehicle into a closed area...  WATERTOWN, MA - APRIL 19: Boston Police mobilize in the parking lot of the Watertown Mall on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Jared Wickerham, Getty Images  WATERTOWN, MA - APRIL 19: Boston Police mobilize in the parking lot...  WATERTOWN, MA - APRIL 19: Boston Police mobilize in the parking lot of the Watertown Mall on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Jared Wickerham, Getty Images  WATERTOWN, MA - APRIL 19: Boston Police mobilize in the parking lot...  WATERTOWN, MA - APRIL 19: Boston Police Commissioner Edward Davis speaks during a media briefing in the parking lot of the Watertown Mall on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Jared Wickerham, Getty Images  WATERTOWN, MA - APRIL 19: Boston Police Commissioner Edward Davis...  WATERTOWN, MA - APRIL 19: Boston Police Commissioner Edward Davis speaks during a media briefing in the parking lot of the Watertown Mall on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Jared Wickerham, Getty Images  WATERTOWN, MA - APRIL 19: Boston Police Commissioner Edward Davis...  WATERTOWN, MA - APRIL 19: Police convene on School and Walnut Street on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Darren McCollester, Getty Images  WATERTOWN, MA - APRIL 19: Police convene on School and Walnut...  WATERTOWN, MA - APRIL 19: Military Police arrive in armoured vehicles at the parking lot of the Arsenal Mall on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Jared Wickerham, Getty Images  WATERTOWN, MA - APRIL 19: Military Police arrive in armoured...  WATERTOWN, MA - APRIL 19: A Watertown Police official speaks during a media briefing in the parking lot of the Watertown Mall on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Jared Wickerham, Getty Images  WATERTOWN, MA - APRIL 19: A Watertown Police official speaks during...  WATERTOWN, MA - APRIL 19: Boston Police mobilize in the parking lot of the Watertown Mall on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Jared Wickerham, Getty Images  WATERTOWN, MA - APRIL 19: Boston Police mobilize in the parking lot...  WATERTOWN, MA - APRIL 19: Police walk down School and Walnut Street on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Darren McCollester, Getty Images  WATERTOWN, MA - APRIL 19: Police walk down School and Walnut Street...  WATERTOWN, MA - APRIL 19: Police convene on School and Walnut Street on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Darren McCollester, Getty Images  WATERTOWN, MA - APRIL 19: Police convene on School and Walnut...  WATERTOWN, MA - APRIL 19: Onlookers take pictures as they watch from windows while SWAT team members search for one remaining suspect at a neighboring apartment building on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Mario Tama, Getty Images  WATERTOWN, MA - APRIL 19: Onlookers take pictures as they watch...  WATERTOWN, MA - APRIL 19: SWAT team members search for one remaining suspect at a residential building on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Mario Tama, Getty Images  WATERTOWN, MA - APRIL 19: SWAT team members search for one...  WATERTOWN, MA - APRIL 19: SWAT team members aim their guns as they search for one remaining suspect at an apartment building on April 19, 2013 in Watertown, Massachusetts. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed at the school's campus in Cambridge. A short time later, police reported exchanging gunfire with alleged carjackers in Watertown, a city near Cambridge. According to reports, one suspect has been killed during a car chase and the police are seeking another - believed to be the same person (known as Suspect Two) wanted in connection with the deadly bombing at the Boston Marathon earlier this week. Police have confirmed that the dead assailant is Suspect One from the recently released marathon bombing photographs. Photo: Mario Tama, Getty Images  WATERTOWN, MA - APRIL 19: SWAT team members aim their guns as they...  Colonel Timothy Albens (C, at microphone), Massachusetts State Police, with Massachusetts Governor Deval Patrick (R) and Boston Police Commissioner Ed Davis (L) speaks to the media at a shopping mall on the perimeter of a locked down area as a search for the second of two suspects wanted in the Boston Marathon bombings takes place April 19, 2013 in Watertown, Massachusetts. AFP PHOTO/Stan HONDA Photo: STAN HONDA, Getty Images  Colonel Timothy Albens (C, at microphone), Massachusetts State...  Massachusetts Governor Deval Patrick (L) speaks to the media at a shopping mall on the perimeter of a locked down area as a search for the second of two suspects wanted in the Boston Marathon bombings takes place April 19, 2013 in Watertown, Massachusetts. AFP PHOTO/Stan HONDA Photo: STAN HONDA, Getty Images  Massachusetts Governor Deval Patrick (L) speaks to the media at a...  New York City Police Commissioner Raymond Kelly, left, and Mayor Michael Bloomberg hold a news conference, Thursday, April, 25, 2013 in New York. The two say the Boston Marathon bombing suspects intended to blow up their remaining explosives in Times Square. They said Dzhokhar Tsarnaev told Boston investigators from his hospital bed that he and his brother had discussed going to New York to detonate their remaining explosives. Photo: Mark Lennihan  New York City Police Commissioner Raymond Kelly, left, and Mayor...  New York Mayor Michael Bloomberg, left, and Police Commissioner Raymond Kelly arrive for a news conference, Thursday, April, 25, 2013 in New York. The two say the Boston Marathon bombing suspects intended to blow up their remaining explosives in Times Square. Photo: Mark Lennihan  New York Mayor Michael Bloomberg, left, and Police Commissioner...  New York City Police Commissioner Raymond Kelly, left, and Mayor Michael Bloomberg hold a news conference, Thursday, April, 25, 2013 in New York. The two say the Boston Marathon bombing suspects intended to blow up their remaining explosives in Times Square. Photo: Mark Lennihan  New York City Police Commissioner Raymond Kelly, left, and Mayor...  New York City Police Commissioner Raymond Kelly, left, and Mayor Michael Bloomberg hold a news conference, Thursday, April, 25, 2013 in New York. The two say the Boston Marathon bombing suspects intended to blow up their remaining explosives in Times Square. Photo: Mark Lennihan  New York City Police Commissioner Raymond Kelly, left, and Mayor...  New York City Police officers patrol in New York's Times Square, Thursday, April 25, 2013. The Boston Marathon bombing suspects had planned to blow up their remaining explosives in New York's Times Square, officials said Thursday. Photo: Richard Drew  New York City Police officers patrol in New York's Times Square,...  A man takes a photo in New York's Times Square, Thursday, April 25, 2013. The Boston Marathon bombing suspects had planned to blow up their remaining explosives in New York's Times Square, officials said Thursday. Photo: Richard Drew  A man takes a photo in New York's Times Square, Thursday, April 25,...  News headlines circle a building in New York's Times Square, Thursday, April 25, 2013. The Boston Marathon bombing suspects had planned to blow up their remaining explosives in New York's Times Square, officials said Thursday. Photo: Richard Drew  News headlines circle a building in New York's Times Square,...  Pedestrians and cars traverse New York's Times Square, Thursday, April 25, 2013. The Boston Marathon bombing suspects had planned to blow up their remaining explosives in New York's Times Square, officials said Thursday. Photo: Richard Drew  Pedestrians and cars traverse New York's Times Square, Thursday,...  A man takes a photo in New York's Times Square, Thursday, April 25, 2013. The Boston Marathon bombing suspects had planned to blow up their remaining explosives in New York's Times Square, officials said Thursday. Photo: Richard Drew  A man takes a photo in New York's Times Square, Thursday, April 25,...  News headlines circle a building in New York's Times Square, Thursday, April 25, 2013. The Boston Marathon bombing suspects had planned to blow up their remaining explosives in New York's Times Square, officials said Thursday. Photo: Richard Drew  News headlines circle a building in New York's Times Square,...
NEW YORK (AP) &acirc;�� The Boston Marathon bombers were headed for New York's Times Square to blow up the rest of their explosives, authorities said Thursday, in what they portrayed as a chilling, spur-of-the-moment scheme that fell apart when the brothers realized the car they had hijacked was low on gas.  New York Police Commissioner Raymond Kelly said Dzhokhar Tsarnaev told interrogators from his hospital bed that he and his older brother decided on the spot last Thursday night to drive to New York and launch an attack.  [...] when the Tsarnaev brothers stopped at a gas station on the outskirts of Boston, the carjacking victim they were holding hostage escaped and called police, Kelly said.  The Middlesex County district attorney's office also is building a murder case against the surviving Tsarnaev for the death of MIT police officer Sean Collier three days after the bombings, office spokeswoman Stephanie Guyotte said.  Investigators and lawmakers briefed by the FBI have said the Tsarnaev brothers &acirc;��  ethnic Chechens from Russia who had lived in the U.S. for about a decade &acirc;�� were motivated by anger over the U.S. wars in Iraq and Afghanistan.  Based on the younger man's interrogation and other evidence, authorities have said it appears so far that the brothers were radicalized via Islamic jihadi material on the Internet instead of any direct contact with terrorist organizations, but they warned that it is still not certain.  [...] in a show of force, police cruisers with blinking red lights were lined up in the middle of Times Square on Thursday afternoon, and uniformed officers stood shoulder to shoulder.  With tens of millions of dollars in federal homeland security funding at stake, Bloomberg and Kelly have repeatedly sought to remind the public that New York remains at the top of terrorists' wish list.