The head of the FBI's Newark office on Friday denied mishandling a man who told agents he'd been trained as a hijacker for Usama bin Laden (search).

The man, identified in media reports as Niaz Khan, walked into the Newark office in April 2000 and told of plans to hijack U.S. airliners.

After his claims were investigated, he was turned over to British authorities and eventually freed. Khan was named Thursday by The Wall Street Journal and "NBC Nightly News," both of which interviewed him. Khan was described as a Briton of Pakistani descent.

The families of Sept. 11 (search) victims cite the episode as another example of lapses by authorities who might have foiled the 2001 attacks if they had only been more vigilant.

Joseph Billy Jr., the agent in charge of the Newark office, said the man's claims were taken seriously.

"An investigation was done on this matter when he came to us," Billy told The Associated Press. "Nothing was discounted. We spent several weeks with him around the clock trying to verify the information that he gave us."

The FBI (search) shared information with other agencies and turned the man over to British authorities, Billy said.

"None of the information that he gave us was ever able to be confirmed or denied," Billy said.

Patty Casazza, whose her husband, John, died in the Sept. 11 attacks, called the FBI's handling of the case "another brand of negligence."

"How many warnings do you have to have until news of a hijacking is to be deemed credible?" she asked.

A House-Senate committee's December 2002 report said the man told the FBI that he had learned hijacking techniques and received arms training in a Pakistani camp and that he was to meet five or six people in the United States.

"Some of these persons would be pilots who had been instructed to take over a plane, fly to Afghanistan, or, if they could not make it there, blow the plane up," the report said.

Although Khan passed polygraph testing, the bureau was unable to verify any aspect of his story or identify his contacts in the United States, the report said.

Khan, 30, said in the media interviews that Islamic radicals lured him into their group in London with the promise of paying his gambling debts.

He said he was taught hijacking basics along with about 30 others in Pakistan, learning how to smuggle weapons through airport security and overpower passengers and crew.

He said he flew into New York to meet a contact but got cold feet, gambled away the money his handlers had given him and, in fear, turned himself in and confessed.