Eight troops presumed dead after search ends for missing Marines

Amphibious vehicle incident leaves nine dead and two others in critical condition

Eight service members are presumed dead after a US Marines amtrac craft, like those pictured returning to shore in 2017, sank near Camp Pendleton in California. (AFP via Getty Images)

A four-day search-and-rescue mission to find seven Marines and a sailor following a training exercise accident has ended, and the missing troops are presumed dead, military officials announced.

On 30 July, an amphibious assault vehicle containing 15 Marines and one sailor sank off the coast of San Clemente Island, California during a routine training exercise. Eight Marines were rescued, one died and two others are in critical condition at a local hospital.

A search effort to recover the others spanned more than 1,000 nautical miles, the Marines announced. The 26-ton craft quickly took on water and began to sink too far below the surface for divers to reach.

"It is with a heavy heart that I decided to conclude the search and rescue effort," Col Christopher Bronzi said on Sunday.

An investigation is underway to determine the cause of the accident. The names of the missing service member are being withheld pending notification to their next of kin.

All of the Marines onboard the craft were attached to the 15th Marine Expeditionary Unit at California's Camp Pendleton near San Diego. Their ages ranged from 19 to 30 year old.

The incident is among the deadliest at the installation involving the craft – also known as amtracs, or amphibious tractors, often used to move troops and supplies from other water crafts to the shore.

Troops on two other amphibious assault vehicles had responded to the scene but could not stop the craft from sinking, Lt Gen Joseph Osterman announced on Friday.

Marine Corps Gen David Berger announced that the branch has suspended waterborne operations from its 800 amphibious assault vehicles out an "an abundance of caution" until the cause of the incident has been determined.

Efforts are underway to recover the missing service members using remote-operated vehicles on the sea floor.

"Our thoughts and prayers have been, and will continue to be with our Marines' and Sailor's families during this difficult time," Col Bronzi said. "As we turn to recovery operations we will continue our exhaustive search for our missing Marines and sailor."