All defense counsel representing detainees facing charges before the military commissions in Guantanamo Bay have been forced to stop work as a result of an internal data breach in the Pentagon’s computer system.

Earlier this month, a “significant amount of defense work” was lost from a common drive, along with “over 500,000 e-mails containing attorney-client privileged communications,” according to a statement from Cmdr. Walter Ruiz, lead defense counsel for the lawyer for Mustafa al Hawsawi, one of four men being tried along with 9/11 mastermind Khalid Sheikh Mohammed.

Defense lawyers also say that more recently, confidential defense files had appeared on prosecution servers, and vice versa.  James Connell, lead counsel for co-defendant Ammar al Baluchi, said that he had seen a prosecution folder on the defense counsel’s drive, but did not open the file.

Connell called the data breach, “simply the latest in a series of revelations of courtroom monitoring,” referring to disclosures in February of audio monitoring devices and controversial searches of the detainees’ legal bins.

Late on Wednesday, Guantanamo Chief Defense Counsel Col. Karen Mayberry ordered all defense counsel to cease using the computer system as it had been found to be insecure.  According to Connell, Col. Mayberry had asked for someone in the Pentagon to identify the specific problems with and solutions to the computer glitches but, “couldn’t get satisfactory information,” and had to make the order.  Cmdr. Ruiz says the order, “essentially cripples our ability to operate,”  and Connell describes the current situation as a “total work stoppage.”

Abd al-Rahim al-Nashiri, accused of plotting the bombing of the USS Cole in 2000, was due to appear before a military commission for a hearing next week, but on Thursday Judge Army Col. James Pohl, granted a defense request to delay the proceedings until the computer problem could be sorted out.

Hearings for the five 9/11 co-defendants were scheduled to resume on April 22, but at least one defense lawyer, James Connell, is filing a similar motion to delay proceedings until the computer system can be secured. Connell said that because of the lack of secure computers, he had to write out his motion to delay the proceedings by hand.

Judge Pohl has received the handwritten motion, and will rule by next Friday on whether the trial of the 9/11 defendants will suffer additional delays.

Update, 5:30 pm EST: In an emailed statement, DoD spokesman Lt. Col. Todd Breasseale denied prosecutors viewed confidential defense emails. “I can tell you unequivocally that NO prosecutor and no member of the privilege review team saw the content of any privileged communications,” he wrote, adding, “the attorney-client privilege ranks among the oldest and most established evidentiary privileges known to our law, and we take this seriously.” Breasseale also noted that the Office of Military Commissions (OMC) suffered “a nearly catastrophic server ‘crash'” that “coupled with satellite latency issues” between U.S. and Guantanamo based computers caused “losses of indiscriminate data” across both the prosecution and defense teams.