Military authorities searched offices of lawyers who represent an Air Force interpreter charged with spying at the Guantanamo Bay, Cuba, prison, one of the man's lawyers said Tuesday.

The Air Force delayed a preliminary hearing for Senior Airman Ahmad I. al-Halabi (search) because of the search and other actions last week that defense lawyers say have interfered with al-Halabi's preparations for his military trial. The hearing, which had been scheduled for Monday, was rescheduled for Jan. 13, the Air Force said in a brief statement issued Tuesday.

Al-Halabi is charged with espionage and aiding the enemy for allegedly e-mailing secrets from the prison camp to an unidentified person and planning to carry notes from some of the prisoners to his native Syria. His lawyers say he is innocent.

Air Force investigators searched the offices of al-Halabi's military lawyers Thursday at Vandenberg Air Force Base in California, his civilian lawyer, Donald G. Rehkopf Jr., said Tuesday. The investigators, who had a military warrant, copied the hard drive of one of the defense lawyers' computers, Rehkopf said.

The search raised the possibility that military defenders, Majs. James Key III and Kim London, could be called as witnesses in proceedings against al-Halabi. That could mean they would have to be taken off the case and new military defense lawyers would have to start from scratch.

Air Force agents also burst into a room where al-Halabi was meeting with his lawyers Wednesday and took hours to return documents and a laptop computer to him Dec. 10 when he was taken from a jail at Vandenberg to Travis Air Force Base, Rehkopf said. Travis, also in California, is al-Halabi's home base, where proceedings against him will be held.

"This conduct by the government is unprecedented and can only be interpreted as a conscious disregard of the attorney-client relationship," Rehkopf said in a statement. He said al-Halabi's defense team vigorously protested the incidents to Col. Barbara G. Brand, the military judge handling the case.

The Air Force statement said Brand delayed the hearing "to allow resolution of questions raised by defense counsel related to the ongoing investigation involving Airman al-Halabi."

An Air Force spokesman did not return a telephone message seeking comment Tuesday.

The airman was the first of four workers at Guantanamo Bay to be arrested as part of an investigation into possible security breaches at the prison for some 660 suspected Al Qaeda or Taliban members.

A former Muslim chaplain at the prison, Army Capt. James Yee (search), has been charged with mishandling classified information, disobeying orders, committing adultery and storing pornography on his military computer. This month, military officials postponed a hearing in his case until January. Yee has pleaded innocent.

A civilian interpreter, Ahmad F. Mehalba (search), was arrested in Boston and charged with lying to federal agents by denying computer discs he was carrying had classified information from Guantanamo. He also has pleaded innocent.

On Nov. 29, Col. Jack Farr, an Army Reserve intelligence officer on six-month assignment to Guantanamo Bay, was charged with transporting secret documents without proper containers and with lying to investigators.