7 Marines and a Sailor Feared Dead as Search Called Off After Training Accident Off Calif. Coast

Marine Expeditionary Force

The search and rescue mission for seven U.S. Marines and one sailor, who went missing following an accident off the coast of Southern California on Thursday, has officially been called off, the Marine Corps 1st Expeditionary Force announced.

On Sunday, the 15th Marine Expeditionary Unit (MEU), I Marine Expeditionary Force (MEF), and the Makin Island Amphibious Ready Group decided to conclude the extensive 40-hour search.

All eight service members are now presumed dead.

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

Marine Corps, Navy, and Coast Guard helicopters, ships and watercraft searched more than 1,000 square nautical miles. Also assisting in search efforts were the USS John Finn, the USS Makin Island, the USS Somerset, and the USS San Diego.

Eleven U.S. Navy SH-60 helicopters and multiple Navy and Marine Corps small boats were also involved as well as the U.S. Coast Guard Cutter Forrest Rednour and a Coast Guard MH-60 Jayhawk helicopter from Coast Guard Sector San Diego.

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

Lenny Ignelzi/AP/Shutterstock San Clemente Island

RELATED: Marine Dead, 8 Missing After 'Tragic' Training Accident in California: 'We Are Deeply Saddened'

On Thursday, 15 Marines and one sailor were inside the amphibious assault vehicle (AAV) during a 15th Marine Expeditionary Unit (MEU) and Makin Island Amphibious Ready Group routine training exercise near San Clemente Island when a "mishap" occurred.

One Marine who served on the 15th MEU, I Marine Expeditionary Force, was pronounced dead at Scripps Memorial Hospital La Jolla.

Two others suffered injuries and were transported to local hospitals, where one was listed in critical condition and the other in stable condition. A total of eight people were recovered from the AAV, while another eight were confirmed missing in the waters.

Search and rescue efforts immediately began by the Marines with help from the U.S. Navy and Coast Guard.

"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," Bronzi said in a statement.

According to the United States Naval Institution, the AAV has been the "primary infantry sea-to-land transport vehicle since the 1970s," and the Marines are currently testing its replacement.