E-mail from the man accused of trying to blow up a trans-Atlantic flight -- including one note in which he described a duty to "remove the oppressive American forces" -- can be used at his trial, a judge ruled Wednesday.

Attorneys for "shoe bomb" suspect Richard Reid had argued the search of Reid's electronic mail account was illegal because the search warrant was overly broad.

But U.S. District Judge William Young ruled that federal agents needed to search Reid's entire Hotmail account because they believed he could have communicated with co-conspirators in code.

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

After his arrest, the FBI obtained a search warrant for Reid's e-mail accounts. Excerpts from his e-mail were included in court documents filed by federal prosecutors.

"What I am doing is part of the ongoing war between Islaam and disbelief," he wrote to his mother two days before his arrest.

"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," he wrote.

Reid's lawyer, Tamar Birckhead, said that when investigators applied for the search warrant, they had no evidence that Reid used his e-mail account for anything except communicating with his mother. The judge said he reserved the right to revise his decision after he reviews new arguments from the defense.

Reid faces eight counts, including a charge of attempting to murder the 197 passengers and crew members on the flight. Trial is set to begin Nov. 4.

The FBI has said it believes Reid had help making the shoe bomb from "an Al Qaeda bomb maker."