The US Navy and Marine Corps has suspended search and rescue efforts for three US Marines missing after their aircraft crashed into the sea off Australia's east coast.
The Marine Corps said they have shifted their operations to recovery efforts in coordination with the Australian Defence Force, which could last several months, and notified the next-of-kin for the three missing Marines.
Twenty-three other personnel aboard the MV-22 Osprey tilt-rotor aircraft had been rescued, the III Marine Expeditionary Force, based in Okinawa, Japan, said in a statement early Sunday.
The plane crashed about 4pm on Saturday off the central Queensland coast at Shoalwater Bay.
It had taken off from the USS Bonhomme Richard and was on regularly scheduled operations when it hit the water in a "mishap", a statement from the US military says.
Small boats and aircraft from the Bonhomme Richard, an amphibious assault ship, immediately swung into action.
US President Donald Trump, who has just begun a 17-day "working vacation" at his New Jersey golf club, has been briefed on the incident by his new chief of staff John Kelly, a White House official told reporters.
Minister for Defence Marise Payne confirmed in a statement late on Saturday night that no Australian Defence Force personnel were on board the aircraft.
The search and rescue operation is being conducted by the 31st Marine Expeditionary Unite and Bonhomme Richard Expeditionary Strike Group, which are on deployment in the Indo-Asia Pacific region.
"The United States are leading the search and recovery effort," Senator Payne said.
She had also briefed Prime Minister Malcolm Turnbull and spoken with US Defense Secretary James Mattis to offer Australia's support.
"Our thoughts are with the crew and families affected," she said.
Queensland Premier Annastacia Palaszczuk offered her government's support to the search and rescue efforts.
"In recent weeks, many Queenslanders have had the opportunity to meet US servicemen and servicewoman visiting as they prepare for the joint military exercise Talisman Sabre in central Queensland.
"On behalf of all Queenslanders, our prayers are with those US military personnel involved in the incident," she said in a statement.
The Osprey aircraft, a tilt rotor aircraft that takes off and lands like a helicopter but flies like an aeroplane, was in Australia for Operation Talisman Sabre, a biennial training exercise involving the defence forces of both countries, at the Shoalwater Bay Training Area. The exercises concluded at the end of July.