After “extensive search and rescue efforts,” US military officials on Tuesday identified three Marines killed in an aircraft “mishap” off the eastern coast of Australia over the weekend.

Twenty-three of the 26 personnel who had been on board MV-22B Osprey were rescued after the incident, which occurred around 4 p.m. local time on Saturday some 18 miles off the coast of Queensland’s Shoalwater Bay, according to officials.

The Marines said on Sunday that they had shifted their search to recovery efforts, and on Tuesday identified those killed as 1st Lt. Benjamin R. Cross, 26, of Oxford, Maine; Cpl. Nathaniel F. Ordway, 21, of Sedgwick, Kansas; and Pfc. Ruben P. Velasco, 19, of Los Angeles, California.

“The loss of every Marine is felt across our entire Marine Corps family. To the families of the brave Marines we lost – there is no way for us to understand what you are going through,” Col. Tye R. Wallace, the commanding officer of the 31st Marine Expeditionary Unit, said in a statement. “What we do know is that your Marines left a lasting impression on the 31st MEU, the Marine Corps, and the world. They will live on forever in our thoughts and our hearts. You will always be a part of the Marine Corps family, and you will remain in our prayers.”

“Operations have now shifted to recovery efforts,” the Marine Corps said in a statement. “The transition comes after teams led continuous sustained search efforts supported by aircraft and ships. As the sea state permits, recovery efforts will be conducted to further search, assess and survey the area, in coordination and with assistance from the Australian Defence Force.”

Royal Australian Navy divers on Tuesday joined the search for the Marines’ remains.

The circumstances surrounding the mishap, which involved an MV-22 Osprey, are still under investigation, the Marine Corps said.

The aircraft was conducting “regularly scheduled operations” when it entered the water, officials said in an earlier statement.

“The aircraft involved in the mishap had launched from the USS Bonhomme Richard and was conducting regularly scheduled operations when the aircraft entered the water,” the statement said. “The ship’s small boats and aircraft immediately responded in the search and rescue efforts.”

A White House official said President Donald Trump was briefed by John F. Kelly, the White House chief of staff, on the situation.

Australian Defense Minister Marise Payne said the incident occurred off the coast of Shoalwater Bay, which is home to a military training area.

Payne said no Australian military personnel were on board the aircraft.

The Australian Broadcasting Corporation reported the aircraft had been in Queensland as part of a joint US and Australian training exercise that ended July 25.

Some 1,250 Marines touched down in Australia in April on a six-month deployment to conduct training exercises with local troops and visiting Chinese forces. Thirteen US aircraft were sent to Australia as part of the deployment, including the tilt-rotor Ospreys, Reuters reported.

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