One Marine is dead and eight others are missing after a training exercise went wrong off the coast of Southern California. A press release from the One Marine Expeditionary Force says the soldier was pronounced dead at a hospital in San Diego last night. Two other Marines are being hospitalized, one in critical condition and one in stable condition. Marine officials say there was a “mishap” Thursday night involving an amphibious assault vehicle near San Clemente Island, involving members of the 15th Marine Expeditionary Unit. Fifteen Marines and one sailor were inside the vehicle when they reported taking on water. Eight of the Marines are still missing. The One Marine Expeditionary Force says search and rescue efforts are underway, with support from the Navy and the Coast Guard.