(CNN) -- Federal agents are conducting a criminal investigation that could affect the trial of Khalid Sheikh Mohammed and four others accused of plotting the 2001 terrorist attacks, Justice Department lawyers told a U.S. military court Monday in Guantanamo Bay, Cuba.
The lawyers, in a filing with the court Monday, acknowledged for the first time that the inquiry existed but also requested more time to determine its scope and how it could affect the planned 9/11 trial.
That request came after preliminary proceedings for the planned military commissions trial were halted recently when defense attorneys for defendant Ramzi bin al Shibh said a member of the defense team was approached by Federal Bureau of Investigation agents and asked to become a confidential informant in an ongoing probe.
Defense lawyers said they believed it was related to what military prosecutors said was the unauthorized publication in January of a manifesto written by Mohammed. The defense viewed the FBI's involvement as causing a potential conflict of interest that could prompt defense lawyers to resign. Such a move could force even more delays of a trial not expected to start until next year, 14 years after the terror attacks.
In the Monday public filing, a special team of Justice Department lawyers set up specifically to handle the dispute said only that the ongoing FBI "preliminary investigation" includes "classified information" but has nothing to do with the publication of the Mohammed manifesto.
The lawyers said that they provided more detailed information in a separate filing with the court but that document would not be made public to preserve the investigation.
"Contrary to the apparent belief of defense counsel ... and the (military) commission.... the FBI preliminary investigation does not pertain to the disclosure of Mr. Mohammed's written communications to third parties," the public court filing said.
The government lawyers asked the military court for 30 days to provide "more complete" information to the military court to address the conflict claims.