SAN CLEMENTE ISLAND - President Donald Trump on Tuesday expressed his condolences to the families of the eight Marines and one Navy sailor who are all presumed dead after an amphibious vehicle sank during a training mission Thursday near San Clemente Island.
Only one of their bodies was found, despite an intense 40-hour search effort.
One additional Marine was rescued, but later died, and two others remain in critical condition, in the aftermath of the incident that occurred 80 miles off the coast of Encinitas.
"It is with a heavy heart that I decided to conclude the search and rescue effort,'' said Col. Christopher Bronzi, the commanding officer of the 15th Marine Expeditionary Unit (MEU), when the search was suspended. "As we turn to recovery operations we will continue our exhaustive search for our missing Marines and sailor.''
The 15th MEU, 1st Marine Expeditionary Force (MEF), and the Makin Island Amphibious Ready Group (ARG) had been working together to try to locate more survivors, but they concluded the search and rescue operation Saturday after 40 hours of seeking across 1,324 square miles.
All Marines involved were identified Monday morning in a statement that said an investigation is underway.
Lance Cpl. Guillermo S. Perez, 20, of New Braunfels, Texas, was pronounced dead at the scene, the statement said. The statement said the presumed dead include, Pfc. Bryan J. Baltierra, 19, of Corona, Calif., a rifleman; Lance Cpl. Marco A. Barranco, 21, of Montebello, Calif., a rifleman; Pfc. Evan A. Bath, 19, of Oak Creek, Wis., a rifleman; U.S. Navy Hospitalman Christopher Gnem, 22, of Stockton, Calif., a hospital corpsman; Pfc. Jack Ryan Ostrovsky, 21, of Bend, Ore., a rifleman; Cpl. Wesley A. Rodd, 23, of Harris, Texas, a rifleman; Lance Cpl. Chase D. Sweetwood, 19, of Portland, Ore., a rifleman; Cpl. Cesar A. Villanueva, 21, of Riverside, Calif., a rifleman.
"I am deeply saddened by the tragic loss of eight Marines and one Sailor during a training exercise off the coast of California," Trump wrote on Twitter Tuesday. "Our prayers are with their families. I thank them for the brave service their loved ones gave to our Nation."
The fatal accident -- which prompted an immediate suspension of AAV water operations -- took place about 5:45 p.m. Thursday, while the crew was en route to a waiting ship following several days of operational maneuvers, said Lt. Gen. Joseph Osterman, commanding general of 1st MEF.
In total, 15 Marines and one sailor had participated in the exercise.
"The amphibious assault vehicle (AAV) they were riding in began to take on water and sank,'' according to a MEF press release.
Seven of the personnel were able to get out of the sinking land and sea-going vehicle and were pulled from the water. Medics took three of them to Scripps Memorial Hospital La Jolla, where one was pronounced dead and the others were admitted in critical but stable condition.
The other five rescued Marines received clean bills of health and returned to their units, officials said.
Crews aboard the USS John Finn, USS Makin Island, USS Somerset and USS San Diego, assisted in the operation. Eleven U.S. Navy helicopters, several smaller USN and Marine Corp. vessels, a U.S. Coast Guard cutter and a chopper from USCG Sector San Diego, also participated in the search for the missing service personnel.
The 26-ton amphibious vehicle went down more than 1,000 yards from a beach on the northwest side of the San Clemente Island in water several hundred feet deep, Osterman said.
"It's really below the depth that a diver can go to,'' Osterman said.
The incident will be the subject of an exhaustive investigation, according to USMC officials.
"Our thoughts and prayers have been, and will continue to be with our Marines' and sailor's families during this difficult time,'' Bronzi said.
"The steadfast dedication of the Marines, sailors, and Coast Guardsmen to the persistent rescue effort was tremendous.''
All of the Marines involved were assigned to the 15th Marine Expeditionary Unit, based out of Camp Pendleton.
The Undersea Rescue Command will now deploy an underwater drone to look for remains on the ocean floor, with support from offshore supply ship HOS Dominator.
San Clemente Island is one of the eight islands that make up the Channel Islands archipelago.
The island is owned and operated by the U.S. Navy and is part of Los Angeles County. It is administered by Naval Base Coronado.
FOX 11's Shelly Insheiwat and Mary Stringini contributed to this report.