When the comedian Steve Rannazzisi has explained his success, which includes seven seasons starring on a popular TV show, “The League,” and a one-hour special this Saturday on Comedy Central, he has frequently attributed it to decisions he made after narrowly escaping the World Trade Center attacks on Sept. 11, 2001.  In elaborate detail, Mr. Rannazzisi, 37, has described working at Merrill Lynch’s offices on the 54th floor of the south tower when the first plane struck the north tower.  “I was there and then the first tower got hit and we were like jostled all over the place,” he told an interviewer in 2009.  He fled to the street just minutes before another plane slammed into his building, he said, and decided that very day that life was too precious to waste opportunities. So he abandoned his New York desk job to pursue a career as an entertainer in Los Angeles.  Nonetheless, he said, he remained affected by his memories of that day.  “I still have dreams of like, you know, those falling dreams,” he told the interviewer.  Confronted by The New York Times this week, though, with evidence that undermined his account, Mr. Rannazzisi, after a day of deliberation, acknowledged on Tuesday that his account was fiction. Actually, he had been working in Midtown that day, and not for Merrill Lynch, which has no record of his employment and had no offices in either tower.  “I was not at the Trade Center on that day,” he said in a statement provided by his publicist, Matthew Labov. “I don’t know why I said this. This was inexcusable. I am truly, truly sorry.”  It was unclear how Mr. Rannazzisi’s admission might affect his standing with Buffalo Wild Wings, which had made him the face of an ad campaign associated with the start of this N.F.L. season and which had featured him in commercials last spring for March Madness.  “We are disappointed to learn of Steve’s misrepresentations regarding the events of September 11, 2001,” Buffalo Wild Wings said in a statement Tuesday night. “We are currently re-evaluating our relationship with Steve pending a review of all the facts.” Comedy Central expressed similar disappointment and said it too had not decided its next step.  But FX Networks, whose FXX carries “The League,” said that while Mr. Rannazzi’s deception had been “upsetting” and “unfortunate,” it still would go forward with him as a character in the show’s final season. It has produced 11 of the 13 episodes, and production of the final two is not expected to be completed until mid-October. “We believe Steve is sincere in his apology and will do everything he can to make amends moving forward,” the network said in a statement.  Mr. Rannazzisi, who declined requests for an interview, said in his statement that once he had lied, he could not figure out a way to undo the damage.  “For many years, more than anything,” he said, “I have wished that, with silence, I could somehow erase a story told by an immature young man. It only made me more ashamed. How could I tell my children to be honest when I hadn’t come clean about this?”  His interviews, though, several of which remain posted on the Internet, show that a decade after the Sept. 11 attacks, Mr. Rannazzisi was still relating a harrowing experience. In a 2011 interview on the podcast “Sklarbro Country,” Mr. Rannazzisi said that he had gotten a good severance package from Merrill Lynch and that he clearly understood that Sept. 11 was a sensitive topic. “I’ve spoken about it before,” he said. “I just don’t ever want to feel like, anyone, I am cashing in or anything like that.”  Mr. Rannazzisi, who is originally from Long Island, is far from the first person whose Sept. 11 account has been exaggerated or, as is the case here, false. The most startling example was a Spanish woman, Alicia Esteve Head, who went by the name Tania Head. She joined the World Trade Center Survivors’ Network support group and went on to become its president, but her story of escape from the 78th floor of the south tower was fabricated. She was believed to be in Barcelona, Spain, on Sept. 11.  Her rationale for suggesting she was there remains no clearer than Mr. Rannazzisi’s. But what is clear is that, since he moved to Los Angeles shortly after the attacks, with his girlfriend, now his wife, his profile has risen steadily. In 2003, he was noticed by the actor Ashton Kutcher, who gave him his first TV role, as a cast member on MTV’s “Punk’d,” according to Mr. Rannazzisi’s website.  From there, Mr. Rannazzisi was cast in several movies and TV sitcoms, including “The League,” about the high jinks of friends in a fantasy football league, where he has played Kevin MacArthur, an assistant district attorney and commissioner of the league.  In 2013, he got a standup special, “Steve Rannazzisi: Manchild” on Comedy Central, the network that helped start the careers of Jon Stewart and Amy Schumer. On Saturday, Mr. Rannazzisi’s new special, “Breaking Dad,” is scheduled to debut on that network.  Many of these milestones are recounted on his website, steverannazzisi.com, though it also incorrectly reported until Wednesday that he was a graduate of the State University of New York at Purchase, a college with a noted reputation in the performing arts. Mr. Rannazzisi is actually a graduate of SUNY Oneonta, where he majored in communications, according to Mr. Labov, who described the discrepancy as an oversight. On Wednesday, the website dropped Mr. Rannazzisi’s affiliation with the Purchase school, describing him now as a SUNY graduate who had majored in theater and film.  As for his Sept. 11 account, Mr. Rannazzisi gave a detailed version to the comedian Marc Maron on his podcast in December 2009, saying he had worked as an account manager for Merrill for a year and a half and had been watching from the street when the second plane struck.  “I couldn’t tell exactly where it went in,” Mr. Rannazzisi said. “So, I called up to the office, and it was pandemonium. They were like, ‘We are on our way down, we are on our way down.’ ”  Mr. Rannazzisi had noted in some interviews that his girlfriend also worked in the south tower on Sept. 11 on the 24th floor but said she had been delayed and never made it to the building. (Actually, Mr. Rannazzisi got that wrong as well. Mr. Labov said on Tuesday that Mrs. Rannazzisi was scheduled to work as a temp on Sept. 11, but in the World Financial Center, nearby, not in the south tower.) When they both got home, he said on the podcast, they decided they would move to Los Angeles.  “We went up to the roof of our building, we smoked a joint and then decided we are going to leave,” he said.  Mr. Rannazzisi gave a similar account on the TV special “Pauly Shore & Friends” in 2009.  Mr. Rannazzisi, sitting on a couch in his home next to his wife who was cradling their baby, told Mr. Shore that the attacks had forced the couple to re-evaluate their lives.  “We decided that we were moving,” he said. “We were like: ‘You know what? I am going to do what I want to do now.’ I wasn’t doing a lot of comedy. I wasn’t doing lot of acting, what I went to school for.”  In recent years, Mr. Rannazzisi played down his account. In a 2013 radio interview on “The Don Geronimo Show,” he corrected the interviewer who suggested he had been in the south tower on Sept. 11.  “I was outside, really,” he said. “I was working downtown at that time.”  That rollback story was also off, but Mr. Rannazzisi sounded contrite on Tuesday in the statement he released about his 9/11 fabrications.  “It was profoundly disrespectful to those who perished and those who lost loved ones,” he said. “The stupidity and guilt I have felt for many years has not abated. It was an early taste of having a public persona, and I made a terrible mistake. All I can ask is for forgiveness.”  One cast member from “The League,” Katie Aselton, came to his defense on Wednesday, suggesting on her Twitter account that Mr. Rannazzisi was a comedian, not a politician, who had made a mistake.  “I love @SteveRannazzisi and my heart goes out to him & his family,” she wrote. “And my heart goes out to everyone he may have hurt. This sucks all around.”  Susan Beachy and Jack Begg contributed research.  A version of this article appears in print on September 17, 2015, on page C1 of the New York edition with the headline: Comic SaysHis Story About 9/11Was a Lie. Order Reprints| Today's Paper|Subscribe
Mr. Rannazzisi, who has a Comedy Central special on Saturday, has often attributed his success to decisions made after surviving the terrorist attacks.