The Marines from AVTB routinely conduct training exercises to test the vehicle’s capabilities and make sure they are performing to the standard. Credit: Wikimedia.

Marine Corps, Navy and Coast Guard services have halted their search for eight missing troops following a deadly Marine amphibious vehicle accident that took place Thursday afternoon off the coast of southern California, The Guardian reported.

Seven other Marines were rescued and are alive while one was killed after their vehicle took on water and sank during a training mission at around 5:45 pm Pacific time on Thursday, US military officials said during a news conference.

“They signaled to the rest of the unit that they were in fact taking on water,” Lt.- Gen. Joseph Osterman said. “Immediate response was provided by two additional amphibious assault vehicles (AAVs) as well as a safety boat,” The Guardian reported.

Two of the rescued Marines were in critical condition at Scripps Memorial Hospital La Jolla while the other five are back aboard their assigned ships, Gen David Berger said.

Officials said the recovery mission is complicated by the vehicle’s location under hundreds of feet of water, beyond the reach of divers, The Guardian reported.

The Marines were wearing combat gear along with inflatable vests when the incident occurred, Osterman said.

“It sank completely,” he said, adding that it was in several hundred feet of water. At “26 tons, the assumption is that it went all the way to the bottom.”

The incident occurred during what the Marine Corps said was a routine training exercise near San Clemente Island. Marines often practice beach assaults there using amphibious troop transport vehicles, The Guardian reported.

“It is with a heavy heart, that I decided to conclude the search and rescue effort,” said Col. Christopher Bronzi, 15th Marine Expeditionary Unit Commanding Officer. “The steadfast dedication of the Marines, Sailors, and Coast Guardsmen to the persistent rescue effort was tremendous.”

All eight service members are presumed deceased.

The armored vehicles can hold more than 20 passengers and up to 250 pounds of equipment, and can weigh as much as 30 tons. They are outfitted with machine guns and grenade launchers.

They look like tanks as they roll ashore for beach attacks, with Marines pouring out of them to take up positions, NBC San Diego reported.

Berger said he suspended all AAV water operations until the cause is determined. He also said AAVs across the fleet will be inspected.

All the Marines involved were assigned to the 15th MEU, which is based at Camp Pendleton, the largest marine base on the west coast of the United States, between Orange and San Diego counties.

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