Beirut, Lebanon ? Before Assem Hammoud and his associates decided to try to bomb New York’s PATH trains, they had considered several other targets: the Golden Gate Bridge and the forests of California, and the Brooklyn Bridge where they would set a huge fire, Lebanese security officials told Newsday.

They eventually settled on the tunnels under the Hudson River, plotting to send suicide bombers to kill thousands of commuters and devastate the U.S. economy, according to two security officials who spoke Saturday on the condition on anonymity.

“They studied different possibilities and they decided to move ahead with an attack on the train tunnels,” one official said. “They thought that would be the most viable plan.”

Lebanese investigators found maps and other information about the two bridges and California forests when they raided Hammoud’s home in Beirut after his arrest on April 27, the official said.

Hammoud, 31, is the alleged mastermind of the plot by eight al-Qaida followers scattered across six countries. He is being held in Lebanon.

U.S. and Lebanese officials unraveled the plan by monitoring Internet chat rooms used by Islamic extremists – long before any of the suspects tried to secure financing or explosives. None had even visited the United States.

U.S. officials said Friday that two other plotters were in custody but refused to say where. The Lebanese officials said that Hammoud was in contact with militants in Iran, Syria, Pakistan, Denmark and Canada, and that the other suspects are in those countries. The five plotters still at large are a Saudi, a Yemeni, a Palestinian, a Jordanian and an Iranian Kurd, according to the officials.

Although Lebanese and U.S. authorities said Hammoud was an al-Qaida operative who had sworn allegiance to Osama bin Laden, they did not outline his alleged ties to that group – or its leaders – when they first announced his arrest Friday. That led some analysts to speculate that Hammoud was part of a new trend in global terrorism: small, localized cells that don’t necessarily take orders from bin Laden or other al-Qaida leaders.

“This is the lone wolf phenomenon, where a small band of like-minded extremists decide to take action on their own,” said Diaa Rashwan, a leading expert on Islamic militancy at the al-Ahram Center for Political and Strategic Studies in Cairo, Egypt. “They might draw inspiration from al-Qaida and bin Laden, but they might not be following direct orders.”

The security officials told Newsday that Hammoud had contact with at least two of 13 men who were arrested by Lebanese authorities in December for belonging to al-Qaida and planning attacks from Lebanon.

The officials said Hammoud was in touch with Hassan Nabaat, a Lebanese, and Hany Shanti, who has Lebanese and Jordanian nationalities. But Lebanese officials have provided few details about those arrested, their relationship to al-Qaida and what attacks they were plotting.

Investigators moved to arrest Hammoud in late April – after keeping him under surveillance for three months – because they concluded that he had obtained a visa to Pakistan and was getting ready to leave. After his arrest, the officials said, he confessed he was to undergo four months of training in Pakistan at an al-Qaida-linked camp.