Officials are investigating the death of a Parris Island (search) recruit from the Marine Corps Recruit Depot early Thursday morning.

The recruit had been training in a 54-hour field training exercise called the Crucible. The exercise, which is a graduation requirement for recruits, is a test of endurance that involves food and sleep deprivation.

The exercise would have ended Thursday morning after a hike back to base. But the recruit did not respond when drill instructors tried to wake him at 2:30 a.m., said spokesman Maj. Ken White.

The trainers attempted to revive him with CPR. He was transported to Beaufort Memorial Hospital where he was pronounced dead at 3:38 a.m.

Department of Defense (search) policy prohibits providing information about the recruit until 24 hours after family has been notified.