1 Marine Dead, 8 More Missing After AAV Accident Off California Coast

assault amphibious vehicle departs the well deck of USS San Diego
An assault amphibious vehicle departs the well deck of amphibious transport dock ship USS San Diego (LPD 22) while conducting the final amphibious assault, during Rim of the Pacific 2016, July 30, 2016. (U.S. Navy photo/Joseph M. Buliavac)

Marine Corps, Navy and Coast Guard assets are searching for eight missing troops following a deadly Marine amphibious vehicle accident that took place Thursday afternoon off the coast of southern California.

The Marines, assigned to the San Diego-based 15th Marine Expeditionary Unit, had been conducting a routine training exercise near San Clemente Island in coordination with the three-ship Makin Island Amphibious Ready Group and other assets assigned to the MEU. Around 5:45 p.m. local time, the amphibious assault vehicle reported taking on water, according to a news release from I Marine Expeditionary Force.

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Of the 15 Marines and one sailor aboard the AAV, eight were able to make it out of the vehicle. One was evacuated to Scripps Memorial Hospital La Jolla near San Diego, where the Marine was pronounced dead. Two more Marines were sent to local hospitals, where they remain. One is in critical condition, and one is stable, according to officials.

Eight service members who were aboard the AAV remain missing. According to the release, the Navy destroyer John Finn, three Navy MH-60 Seahawk helicopters and small boats from the amphibious ships Makin Island, Somerset and San Diego are participating in the search. The Coast Guard cutter Forrest Rednour and an MH-60 Jayhawk helicopter from Coast Guard Sector San Diego are also assisting.

Marine Corps officials declined to identify the Marine who died, citing a 24-hour notification period for family members.

"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," Col. Christopher Bronzi, 15th MEU commanding officer, said in a statement.

Amphibious assault vehicles, which move on tank-like tracks and can operate on land and swim in water, are used to transport Marines from ship to shore. They've been in use by the Marines since the early 1970s and are currently set to be replaced by the amphibious combat vehicle, now in development.

In January 2011, one Marine died when an AAV sank off the coast of Camp Pendleton during a training operation. The other five Marines aboard were able to escape.

-- Hope Hodge Seck can be reached at hope.seck@military.com. Follow her on Twitter at @HopeSeck.

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