Three US Marines are killed in a military plane crash during a training exercise in the Northern Territory, Australia

At least three US Marines have died in a plane crash in Australia’s Tiwi Islands, north of Darwin, US military officials said on Sunday.

Naval Rotational Force-Darwen said in a statement that five others were in a “serious condition” and had been taken to the Royal Darwin Hospital.

The statement added that 23 Marines were on board an MV-22B Osprey helicopter during a routine exercise when it crashed on remote Melville Island, 60 kilometers off the coast from Darwin.

“Marines were on board flying in support of the Predators Run exercise. Recovery efforts are continuing,” the statement read.

Naval Rotational Force-Darwin said the cause of the accident was being investigated.

Northern Territory Police Commissioner Michael Murphy said the crash occurred just after 9 am (0100 GMT).

Australian Prime Minister Anthony Albanese called the incident “tragic” and said no Australian personnel were involved.

“Our focus as a government and as the Department of Defense is very much on incident response and making sure all support and assistance is provided at this difficult time,” the prime minister said during a previously scheduled news conference in Western Australia.

About 2,500 individuals from Australia, the United States, the Philippines, Indonesia and Timor-Leste are taking part in the “Predator Race 2023” exercise.

The Australian Ministry of Defense said the “Bell Boeing V-22 Osprey” crashed on Melville Island during the “Predators Run” exercise involving the armies of the United States, Australia, Indonesia, the Philippines and East Timor.

“Initial reports indicate that the incident involved personnel from the US Department of Defense and that members of the Australian Defense Force were not involved,” the ministry said in a statement sent by email.

Albanese said his government was focused on providing support. Albanese, speaking at a previously scheduled news conference, declined to provide details about the accident or rescue efforts.

“Our focus as a government and as a Department of Defense is very much on incident response and making sure all support and assistance is provided at this difficult time,” he said.

The United States and Australia, a major ally in the Pacific region, have stepped up their military cooperation in recent years in the face of an increasingly aggressive China.

Last month, four Australian soldiers were killed during a major bilateral exercise when their helicopter crashed into the ocean off the coast of Queensland.