Defense lawyers asked a judge Wednesday to bar as evidence e-mail seized from a man accused of trying to blow up a jetliner with a bomb hidden in his shoes.

Included among the electronic messages is one in which Richard Reid said he had a duty as a Muslim to "help remove oppressive American forces."

In a motion filed Wednesday, Reid's attorneys argued the e-mail seizure after Reid's arrest was illegal because the FBI did not have probable cause for a search warrant. They asked that prosecutors be prohibited from using the e-mail at Reid's trial.

Reid, a British citizen, is charged with trying to blow up an American Airlines flight from Paris to Miami on Dec. 22. Passengers and crew members restrained him after he allegedly tried to light a fuse protruding from his shoe. The flight was diverted to Boston.

Excerpts from the e-mail messages were included in court documents filed by federal prosecutors.

In one message to his mother two days before his arrest, Reid wrote: "What I am doing is part of the ongoing war between Islaam and disbelief, (and as such a duty upon me as a Muslim)."

In another, Reid says he sent his mother what he described as his will "so you can see that I didn't do this act out of ignorance nor did I just do it because I want to die, but rather because I see it as a duty upon me to help remove the oppressive American forces from the Muslim land and that this is the only way for us to do so as we do not have other means to fight them."

The spelling and punctuation are consistent with the e-mail.

The FBI said in its search warrant application that Reid told authorities that he built the bomb using instructions he obtained from the Internet. But his lawyers claim the agency "had no evidence that the defendant used his e-mail account for anything besides communication with his mother."

Reid's lawyers did not immediately return a message left at their office.

Samantha Martin, a spokeswoman for U.S. Attorney Michael Sullivan, declined to comment. She said prosecutors would file a written response within 10 days.

Director Robert Mueller has said the FBI believes that "an Al Qaeda bomb maker" constructed the shoe bomb. Authorities say Reid was ruled out as the source of a human hair and palm print found on the bombs.

Reid's trial is scheduled to begin Nov. 4. He faces eight counts, including a charge of attempting to murder the 197 passengers and crew members on the flight.