One U.S. Marine has died, another is in critical condition and a rescue operation is underway for eight more service members after a training exercise "mishap" with an amphibious assault vehicle off the coast of Southern California on Thursday.
The deceased Marine, whose name is being withheld for 24 hours so that the family can be informed, was pronounced dead at a hospital in San Diego on Thursday, according to a press release early Friday by the I Marine Expeditionary Force.
The Marine in critical condition and another injured Marine in stable condition were taken to hospitals for treatment. The missing included 7 Marines and one sailor, officials said.
Gen. David Berger said at a news conference Friday afternoon, "The vehicle sank after taking on water."
Fifteen Marines and one sailor were inside the vehicle for the training exercise near San Clemente Island on Thursday, when they reported taking on water at about 5:45 p.m., the release said.
"When they AAV began to take on water they signaled to the rest of the unit that they were in fact taking on water," said Lt. Gen. Joseph L. Osterman.
Two amphibious assault vehicles and a safety boat were nearby, he said. All the Marines had floatation devices and some of those rescued were found bobbing with the gear successfully deployed, Osterman said.
The 26-ton vehicle appeared to sink in "several hundred feet of water" more than 1,000 meters from the northwest corner of the island, he said.
Wave heights in Southern California have been small -- 2 feet maximum -- and water temperatures have been unusually cold, from 60 degrees to the mid 60s along the coast due east of the island.
"The Marines were all in their normal combat gear," the lieutenant general said.
He described the underwater geography as "below the depth that a diver can go to."
However, Marine Corps officials have not given up hope on rescuing service members alive. "We're still looking for them," Osterman said.
Officials said the amphibious assault vehicles date back to the 1970s but often have been rebuilt multiple times, with emergency lighting added.
Search-and-rescue efforts were ongoing early Friday to find the eight service members who were missing. The Navy and Coast Guard were assisting in the search.
“We are deeply saddened by this tragic incident. I ask that you keep our Marines, Sailors, and their families in your prayers as we continue our search,” said Col. Christopher Bronzi, 15th Marine Expeditionary Unit Commanding Officer, on Twitter.
The I Marine Expeditionary Force said it would investigate the incident.