At least three Australian defence personnel were aboard the US submarine that sank an Iranian warship with a torpedo in the Indian Ocean, country’s prime minister Anthony Albanese said on Friday.
The defence personnel were present on the submarine but did not take part in the attack which sank an enemy vessel, Mr Albanese said.
A US submarine sank an Iranian warship off the southern coast of Sri Lanka, killing dozens of sailors and dramatically widening Washington's pursuit of the Iranian navy. Sri Lanka's deputy foreign minister identified the warship as the frigate IRIS Dena, and said it was heading back to Iran from an eastern Indian port.
The attack happened hundreds of miles across the Indian Ocean from the Gulf, where US and Israeli forces are striking Iran and Tehran is retaliating with missile and drone attacks.

Speaking to Sky News, Mr Albanese said that Australians were on board as part of training linked to the Aukus defence pact between Australia, the US and the UK in aiding Australia acquire and build nuclear-powered submarines.
“We wouldn't normally confirm such an issue, but given our [National Security Committee] meetings and the public interest, I can confirm that there were three Australian personnel on board that vessel," the Australian politician said.
"These are long-standing third-country arrangements that have been in place for a long period of time, and what they do is ensure that Australian Defence Force personnel, where they are embedded in third countries' defence assets, they act in accordance with Australian law, Australian policy, and that is, of course, taking place across the board,” he said.
Australia has deployed dozens of its personnel on US fast-attack submarines based out of Pearl Harbour to prepare Australia for acquiring its own nuclear-powered submarines under the Aukus agreement.
More than 100 Australian Defence Force personnel are training within the US under the preparation to rotate through.
About one in 10 crew members serving on US nuclear-powered attack submarines is an Australian defence personnel, the ADF said, reported ABC News.
A close ally of the US, Australia has maintained that it will steer clear from any military role in the major conflict between the US and Iran but will back international efforts to prevent Iran from developing a nuclear weapon.

Mr Albanese said Australia was “comfortable” with assessing that Iran posed a threat on three levels, responding to a question on implications for international law in the US and Israeli strikes on Iran.
Iranian foreign minister Abbas Araghchi accused the US Navy of committing an “an atrocity at sea” in sinking the frigate and said on social media on Thursday that the United States “will come to bitterly regret” the attack.
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