SEATTLE — A sailor who died in an apparent accident on the nuclear missile-carrying submarine USS Nebraska off Hawaii has been identified.

A Navy news release Tuesday identified the sailor as 21-year-old Machinist Mate 3rd Class Michael A. Gentile of Fairfield, Maine. He joined the Navy in 2005 and was previously assigned to the Alaska, another one of the Navy’s 560-foot Trident nuclear-powered subs.

Few details have been released on what happened Saturday while the Bangor, Wash.-based sub was beneath the surface of the ocean.

The Navy Times quoted the Norfolk, Va.-based Naval Safety Center as saying Gentile became “entangled and pinned” in ship’s rudder ram during a cleaning evolution.

Navy officers have said Gentile was given emergency medical treatment aboard the sub and was placed on a medical helicopter, but he died before reaching a hospital.

The Nebraska carriers ballistic missiles armed with nuclear warheads.