A Tanzanian who overstayed his visa after training as a commercial pilot was detained on immigration charges after his name was found on a document in a cave in Afghanistan, the FBI said.

Officials said Thursday there was no evidence to suggest Issaya Nombo, 44, was involved in terrorist activity.

"It is premature, grossly so, to say he's connected with 9/11," said Frank Perry, special agent in charge of the FBI's Raleigh office. "There is no information whatsoever to link him with terrorism."

During interviews with federal agents, Nombo said he was Roman Catholic, suggesting an unlikely alignment with Muslim extremists, Perry said. He also appeared to be the same Issaya Nombo who worked as a South African Airways pilot but left before being sentenced last spring on charges related to buying papers to pass a pilot's exam, Perry said.

Nombo was arrested by federal agents Monday in suburban Apex, along with two other people. Perry declined to describe the others but said all three were being held on visa violations.

Two U.S. officials in Washington, speaking on condition of anonymity, said Nombo was found with a counterfeit green card and Social Security card.

The document found in Afghanistan had appeared on the Web site of Voyager Aviation in Titusville, Fla., which includes a congratulatory note to Nombo and two other students for completing their training.

U.S. and allied soldiers found the document while combing caves abandoned after battles with Taliban and Al Qaeda fighters. The names of other foreign nationals as well as Americans were found in the same place and were being checked, Perry said.

Other details of Nombo's case also attracted interest and led to an urgent FBI order to find and question him, Perry said.

Nombo said he was from Dar es Salaam, where the U.S. Embassy was bombed in 1998, an attack blamed on Al Qaeda and Usama bin Laden. Several hijackers in the Sept. 11 attacks also had taken flight lessons in Florida, including learning how to pilot commercial airliners.

Nombo's visa, issued for students attending technical schools, required that he leave the United States by Aug. 23, 2001. Immigration officials believe he left Florida after his flight training and moved to North Carolina.

After U.S. intelligence officials found Nombo's name on the document, the INS checked the name against its records and discovered the expired visa, a U.S. official said.

Perry said Nombo was in Immigration and Naturalization Service custody.

Voyager Aviation owner Gary Evans confirmed that Nombo earned airline transport pilot certification at the school, but he declined to provide details. He said the airline transport pilot license is the highest level of commercial pilot certification, earned only "after you've got a good few years' experience."

Also Wednesday, a man who spent time with some of the Sept. 11 hijackers pleaded guilty in U.S. District Court in Alexandria, Va., to two counts of document fraud unrelated to the attacks.

Eyad M. Alrababah, 29, of Bridgeport, Conn., came forward Sept. 29 after seeing mug shots of the hijackers. He told the FBI he had spent time with the hijackers but didn't know of their plans. He has been detained since then, initially as a material witness.

Authorities suspect Alrababah informed the hijackers that they might obtain fraudulent ID cards in Virginia through lax regulations at the Department of Motor Vehicles.

Seven hijackers got fake IDs from the Virginia DMV through a loophole that allowed people to obtain drivers' licenses and ID cards without proof of residency or identity by submitting sworn statements. That loophole was closed 10 days after the attacks.

The two counts against Alrababah allege that he helped a New Jersey man, Abdel Rahman Omar Tawfiq Alfauru, obtain a fake ID in July 2000.

Alrababah could face up to 30 years in prison, but would likely receive just a fraction of that time.