Helicopters and boats ranging from inflatables to a Navy destroyer were headed into a Saturday search for eight people missing after their Marine landing craft went down in hundreds of feet of water off the Southern California coast.
“Literally every asset we have available" was searching for seven Marines and a Navy corpsman, Lt. Gen. Joseph Osterman, commander of the 1st Marine Expeditionary Force, said Friday.
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They were aboard an amphibious assault vehicle that was heading back to a Navy ship Thursday evening after a routine training exercise when it began taking on water about a half-mile (0.8 kilometers) from Navy-owned San Clemente Island, off of San Diego.
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Other assault vehicles quickly responded but couldn't stop the 26-ton, tank-like vehicle from quickly sinking, Osterman said.
“The assumption is that it went completely to the bottom” several hundred feet below, Osterman said. That was too deep for divers to reach and the Navy and Coast Guard were discussing ways to reach the sunken vehicle to get a view inside it, Osterman said.
Eight Marines were rescued from the water but one later died and two remained in stable condition at a hospital, authorities said.
All the Marines were attached to the 15th Marine Expeditionary Unit (15th MEU), based at nearby Camp Pendleton. They ranged in age from 19 to early 30s and all were wearing combat gear, including body armor, and flotation vests, Osterman said.
On Saturday, the 15th MEU said it notified all families of the Marines and Sailor who were involved in the tragedy.
The vehicle, known as an AAV but nicknamed an “amtrac," for “amphibious tractor" is used to take Marines and their gear from Navy ships to land.
The sunken craft, one of 13 involved in the exercise, was designed to be naturally buoyant and had three water-tight hatches and two large troop hatches, Osterman said.
The vehicles have been used since 1972, and continually refurbished. Marine Corps officials said Friday they did not know the age or other details of the one that sank.
The Marine Corps commandant, Gen. David Berger, suspended waterborne operations of more than 800 amphibious assault vehicles across the branch until the cause of the accident is determined. He said the move was out of “an abundance of caution.”
The accident marks the third time in recent years that Camp Pendleton Marines have been injured or died in amphibious assault vehicles during training exercises.
In 2017, 14 Marines and one Navy sailor were hospitalized after their vehicle hit a natural gas line, igniting a fire that engulfed the landing craft at Camp Pendleton.
In 2011, a Marine died when an amphibious assault vehicle in a training exercise sank offshore of the camp.