Three U.S. Marines are missing after an MV-22 Osprey from the 31st Marine Expeditionary Unit "entered the water" Saturday off of Australia's east coast.
In a statement, III Marine Expeditionary Force, said that following a "mishap," 23 out of 26 personnel aboard had been rescued and that a search and rescue mission was underway for the remaining three.
The "ship's small boats and aircraft from the 31st Marine Expeditionary Unit and Bonhomme Richard Expeditionary Strike Group are conducting the search and rescue operations," tweeted III Marine Expeditionary Force, based in Japan.
The MV-22 Osprey "had launched from the USS Bonhomme Richard (LHD 6) and was conducting regularly scheduled operations when the aircraft entered the water," said the Marines.
The unit was in Australia as part of a regularly scheduled deployment.
NPR's Scott Horsley reports that President Trump has been briefed on the incident by his Chief of Staff John Kelly.
The V-22 Osprey is a combination aircraft, says its maker Boeing, with helicopterlike rotors allowing it to hover; once airborne, it can convert to a fixed-wing plane capable of high speeds and altitudes.
Saturday's incident comes a few weeks after a Marine Corps refueling aircraft crashed in Mississippi, killing all 16 people aboard.
This is a developing story. We will update as the situation develops.