Soldiers from U.S. Marines and Japan's Ground Self-Defense Force attend their joint exercises that are intended to recover an…
FILE - Soldiers from U.S. Marines and Japan's Ground Self-Defense Force attend their joint exercises that are intended to recover an island in San Clemente Island, California, in this photo taken and provided by Kyodo, Feb. 9, 2013.

The U.S. Marines says it has ended the search and rescue mission for seven missing Marines and one Sailor following an accident in Southern California. All the service members are presumed dead. 

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

“As we turn to recovery operations, we will continue our exhaustive search for our missing Marines and Sailor,” Bronzi said.   

Fifteen Marines and one Sailor were participating in a routine training exercise Thursday off the coast of San Clemente Island, California, when the amphibious assault vehicle (AAV) they were riding in began to take on water and sank. Sixteen service members participated in the exercise.  Eight Marines were rescued, one died, and two others are in critical condition at a local hospital.   

The accident is under investigation. 

Marines frequently practice beach attacks using amphibious troop transport vehicles.