The search and rescue operation for eight U.S. servicemen who went missing last week after their landing craft sank in hundreds of feet of water off San Clemente Island in California during a training exercise has ended. The seven Marines and one sailor are presumed dead, officials announced Sunday.

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

Helicopters, ships and boats searched more than 1,000 square nautical miles, but it was determined that there was little probability of a successful rescue. On Thursday, the 26-ton amphibious assault vehicle carrying 15 Marines and one Navy sailor sank after taking on water.

One Marine was taken to Scripps Memorial Hospital La Jolla and later died. Two others were injured and remain hospitalized. Five other service members were rescued.

Los Angeles Times