The Armed Forces Medical Examiner's Office says autopsies have been performed on a sailor and a civilian who died in a shootout aboard a Navy destroyer.

Office spokesman Paul Stone says the autopsies were conducted at Naval Medical Center Portsmouth on Tuesday.

The shooting deaths occurred Monday night at Naval Station Norfolk. The Navy has said Petty Officer 2nd Class Mark Mayo was killed by a civilian truck driver who had disarmed the USS Mahan's petty officer of the watch and used her weapon to fire the fatal shots. The Navy has not released the name of the civilian, who was killed by Navy security.

Navy officials have said there's no indication the attack was planned. Stone says it could take weeks before autopsy results are provided to investigators.