Lebanese authorities found maps and bombing plans on the personal computer of an al-Qaida loyalist accused of plotting to attack New York train tunnels, and a U.S. official disclosed that he had visited the country at least once.

Port Authority Police Lt. John Ryan walks into the PATH train tunnel under the World Trade Center disaster site in this April 16, 2002 file photo in New York. Authorities thwarted an alleged terrorist plot to use suicide bombers in the PATH tunnels which extend under the Hudson River and link New Jersey with lower Manhattan. The terrorists believed that by bombing the train tunnels, they could unleash a flood on Lower Manhattan, including Wall Street, said the official, who spoke on condition of anonymity because the investigation is ongoing. [AP]

Acting Lebanese Interior Minister Ahmed Fatfat described the information found on 31-year-old Assem Hammoud's computer as "very important."

"It contained maps and bombing plans that were being prepared," Fatfat said in a local television interview.

In the U.S., a federal law enforcement official, speaking on condition of anonymity because the investigation is ongoing, said Hammoud had visited the United States at least once -- a trip to California six years ago.

The official said Hammoud had a legitimate visa for a brief stay, and was believed to have been visiting either family or friends. The visit occurred long before authorities say the tunnel plot began to unfold.

Authorities are still trying to trace Hammoud's steps during that trip but say they have no record of him going to New York. They have not ruled out the possibility that Hammoud had come to the country using different names.

Lebanese security officials told The Associated Press that they obtained "important information" from Hammoud's computer and CDs seized from his office at the Lebanese International University, where he taught economics.

"This information helped the investigators make Hammoud confess to his role in plotting a terror act in America," one Lebanese official said, speaking on condition of anonymity because of the sensitivity of the case.

Hammoud, who has used the alias Amir Andalousli, has been in Lebanese custody since April. Two others also are in custody in the case, which U.S. investigators said was disrupted after coordinated efforts with officials in six other countries. Five suspects are at large.

The FBI said the suspects are alleged to have planned to attack trains under the Hudson River using suicide bombers and backpack bombs. The plan, which authorities said the suspects hoped to carry out in October or November, was to flood lower Manhattan by attacking the tunnels -- used by tens of thousands of commuters each day.

But the plot was only in the planning stages, and the suspects had not purchased any explosives or traveled to the U.S. as part of the scheme.

"We received information from the FBI in April about an attempt to plot a terror act in New York City through Internet communications in Lebanon," Fatfat said in the interview Saturday. "Based on this information, security forces acted and arrested Mr. Assem Hammoud."

Officials said Hammoud confessed to the plot, and to swearing allegiance to al-Qaida leader Osama bin Laden.

The Lebanese newspaper As-Safir reported that a Syrian suspect had been lured to Libya and arrested there, along with a third suspect whose nationality was unknown.

Other suspects still at large include a Saudi, a Yemeni, a Jordanian, a Palestinian, and an Iranian Kurd, As-Safir said.

The suspect's family denied that he had any al-Qaida links. His mother, Nabila Qotob, said Hammoud was an outdoorsy person who drank alcohol, had girlfriends and bore none of the hallmarks of an Islamic extremist.

Hammoud studied at Concordia University in Montreal for seven years beginning in 1995, university spokeswoman Chris Mota said Sunday. He graduated with a bachelor's degree in commerce in 2002.