At least four people were feared dead on Saturday after an Australian Defence Force (ADF) helicopter crashed into the ocean off the coast of Queensland, the Defence Minister said.
The helicopter was taking part in a biennial Talisman Sabre military exercises between the US and Australia.
The helicopter ditched into the waters close to Hamilton Island late on Friday night, Richard Marles said in a press conference.
"The four air crew are yet to be found," Marles said, adding that the search and rescue continues.