IN HIS FIRST INTERVIEW, FBI UNDERCOVER TELLS HOW HE INFILTRATED AL QAEDA AND THWARTED TERROR ATTACKS PLANNED FOR NEW YORK AND TORONTO, THIS SUNDAY ON "60 MINUTES"

The FBI's Tamer Elnoury Also Tells Scott Pelley How Terrorist Told Him at Ground Zero "That This Place Needs Another 9/11"

In his first interview, the FBI undercover operative who thwarted an al Qaeda attack on a railroad bridge targeting Americans traveling to Toronto reveals how he infiltrated the terrorist group. He also reveals the same attacker was planning to bomb Times Square during a New Year's Eve celebration. Tamer Elnoury (the name is an alias) tells his story to Scott Pelley in disguise to hide his real identity, on 60 MINUTES Sunday, Oct. 22 (7:30-8:30 PM, ET/7:00-8:00 PM, PT) on the CBS Television Network

Tamer Elnoury works for the FBI's National Security Covert Operations Unit and is one of only a handful of undercovers who is both Arab and Muslim. No member of the unit has spoken before. He's written a book, American Radical, which has been cleared by the FBI.

Elnoury, who came with his family from Egypt when he was 4 years old, says he wrote the book and is doing the 60 MINUTES interview because he wants Americans to understand that Muslims like him are risking their lives to defend the United States. "We're not at war with Islam. We're at war with radicals. I am a Muslim. I am an American. And I've been serving my country for 22 years and counting. And I am appalled at what these animals are doing to my country while desecrating my religion."

Elnoury is one of the many legends he used. A legend is an elaborately crafted identity the FBI gives its undercover operatives. In this case, they made him a wealthy Arab-American real estate investor who accidently meets his al Qaeda contact on a plane. Seated near Chiheb Esseghaier - a terrorist the FBI had been surveilling - Elnoury clearly looked Middle Eastern, and the terrorist reached out to him in Arabic. The plan worked. "I crafted my legend and made myself recruitable. I wanted him to choose me," Elnoury tells Pelley. "I wanted him to go to bed that night wondering what he could do to become my friend."

Elnoury befriended Esseghaier over 10 months, establishing a relationship during which the terrorist twisted the Koran's meaning to recruit him. The terrorists were thorough in their vetting of him. "'What do you do? How do you do it? Is it commercial real estate? Is it residential? What do you do when you fly here? What do you do here?' It sounded like an interrogation," Elnoury says.

Esseghaier recruited Elnoury into a plot to derail a train with hundreds of passengers coming from New York to Toronto while it crossed a bridge. The investigation took a turn when Esseghaier claimed there was an "American sleeper" - a hidden al Qaeda agent in the United States. Elnoury and the FBI tried to learn the identity of the alleged American sleeper. But shortly after the Boston Marathon bombing, Canadian officials who were part of the joint investigation wanted Esseghaier taken down. He and an accomplice were arrested, tried and convicted, then sentenced to life.

Tamer Elnoury nearly blew his cover during a dramatic meeting at Ground Zero. Esseghaier wanted to visit the site of the 9/11 attack, and while he was there, he put his arm around the FBI undercover and said: "'Tamer, this place needs another 9/11, and we're going to give it to 'em.' I saw red at that moment. It was the hardest time in my career to stay professional," he tells Pelley. "Here I am on hallowed ground, and he said that to me. At that very moment, I could feel a pen in the pocket of my jacket. I envisioned stabbing him in the eye and dropping him dead right where he stood."

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