NEW FAIRFIELD, Connecticut (AP) -- A fifth-grade teacher fatally shot a masked teenager in self-defense outside his neighbor's house during what he thought was an attempted burglary and then discovered it was his son, state police said.  The killing of 15-year-old Tyler Giuliano shortly after midnight Thursday left his quiet Connecticut town of New Fairfield reeling in confusion and grief. The teen's father, Jeffrey Giuliano, is a popular fifth-grade teacher in the community, where there is very little violent crime.  The neighbor, who is the teen's aunt, was alone in her house and believed someone was breaking in. She called the teen's father, who lives next door. He grabbed a gun, went outside, confronted someone wearing a black ski mask and black clothing and fired when the person went at him with a shiny weapon in his hand, police said.  When police arrived, the teen was lying in the driveway of the woman's home with gunshot wounds and a knife in his hand. His father, in T-shirt and shorts, was sitting on the grass. The teen was pronounced dead at the scene, police said.  An officer pulled back the ski mask. It was unclear if Jeffrey Giuliano already knew it was his son. It was also unclear if the teen was trying to burglarize the house or if it was some type of prank gone wrong.  "All in all it's a tragedy," state police spokesman Lt. J. Paul Vance said.  Jeffrey Giuliano hadn't returned a message seeking comment on what happened. No one responded to knocks on the front door at his home or his sister's.  No charges have been filed.  John Hodge, the top elected official of the town of nearly 14,000 people some 50 miles (80 kilometers) from New York City, doesn't recall another killing in his eight years on the job. "You certainly don't expect it to happen in your own small hometown where there's very little crime."  The Giuliano home has a three-car garage, with a long, circular driveway near the end of a street. A pumpkin was set out in front of the home for Halloween.  On Friday, a blue crime scene tent covered evidence in the driveway where Tyler was pronounced dead; two white rocking chairs stood empty on his aunt's front porch next to a stack of firewood.  Spokesman Lt. J. Paul Vance said Friday that police were investigating whether the gun used was registered. That will take at least a week. Police were also looking for leads into whether Tyler, described as an easygoing teen who loved flying and was in the Civil Air Patrol, was going to burglarize the home or meant to carry out a prank. There was no immediate word on whether he had been in trouble before.  The high school stayed open late Thursday to provide grief counseling for students and parents.  "The community is deeply saddened, and our hearts go out to all the family members," said Alicia Roy, the superintendent of schools in New Fairfield.  She said Giuliano is a longtime resident who offers summer music and zoology camps for his students at Meeting House Hill School and plays in a band that raises a lot of money for charity.  "He wanted to teach in the community he grew up," she said. "He connects with the students. He's a caring person. Very interactive class."  Brian Wyckoff, 17, once had him as a teacher, and was a classmate of Tyler.  He said "Mr. G," as known around school, loves animals, and keeps snakes in his classroom.  "He was always walking around with a smile on his face. He always says "Hi" to everyone," Wycoff said.  Tyler was a student at New Fairfield High School, a short walk from the neighborhood where he was killed. Roy said he enjoyed spending time with his family. During a storm last year, he volunteered at a shelter set up the local high school, helping to serve meals and set up cots.  Roy said Tyler especially enjoyed flying gliders and single-engine planes out of Danbury airport.  "He would fly as many hours as possible," she said.  "He was a nice kid," said Wyckoff, who said Tyler wasn't in his circle of friends and that the slain teen was quiet and seemed a little shy.  The father played guitar in a local rock band, Split Decision. The band has a show scheduled Sunday to benefit a local charity.  Reached by telephone, keyboardist Lisa Tramazzo, who said she is also a teacher, and bass player Greg Gilroy both declined to talk about Giuliano.  "Nobody is going to answer your questions," Tramazzo said Friday.  An autopsy was planned. There was no word on funeral services.  Associated Press reporter Dan Sewell reported from Cincinnati. Pat Eaton-Robb and Stephen Singer reported from Hartford, Conn.
Police say what appeared to be an attempted late-night burglary turned tragic when a father shot his son.