(AP)—The lawyer for a man accused in an attack on a U.S. warship says a Pentagon computer server failure may have resulted in the loss of a huge amount of data needed by the defense.

Lawyer Richard Kammen also says that more than 500,000 emails from military tribunal defense lawyers were mistakenly turned over to prosecutors.

Kammen has asked a military judge to cancel a hearing next week at the U.S. base in Guantanamo, Cuba for the prisoner charged in the attack on the USS Cole because of the server failure and alleged email breach.

The Pentagon has not filed a formal response to the accusations and a spokesman declined comment Wednesday because the issue is being litigated in court.

Al-Qaida bombed the Cole in 2000, killing 17 crew members.

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