Updated

The Lebanese man accused of plotting to destroy and flood Hudson River train tunnels also discussed the possibility of setting wildfires in California to inflict harm on the U.S., a federal official said Monday.

The official, speaking on condition of anonymity because the investigation is ongoing, said wildfires were "only part of their planning discussions. No steps were taken to carry it out."

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The official also said that Assem Hammoud "raised" the possibility of using backpacks on New York subways to carry explosive devices and attack the transit system.

The possible fire plot and backpacks — first reported by Newsday and the Los Angeles Times — were among several new allegations to emerge in recent days about the 31-year-old Hammoud, who was arrested in Lebanon in April.

He and seven others are accused of plotting to bomb tunnels used by tens of thousands of commuters each day in New York and New Jersey. Authorities said the plot was disrupted in its early stages, and none of the suspects had traveled to the U.S. as part of the scheme or even purchased any explosives.

The plan, which authorities said the suspects hoped to carry out in October or November, was to flood lower Manhattan by attacking the tunnels.

Authorities also said they found maps on the computer of Hammoud, an alleged Al Qaeda loyalist who was said to have visited California six years ago. Authorities are still trying to trace Hammoud's steps during that trip but say they have no record of him going to New York.

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.

Hammoud's family denied that he had any Al Qaeda links. His mother, Nabila Qotob, said Hammoud was an outdoorsy person who drank alcohol and had girlfriends — none of the hallmarks of an Islamic extremist.

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