Three Australian personnel aboard a United States submarine were reportedly sent to their cabins during an operation that sank an Iranian warship off the coast of Sri Lanka last week. The submarine launched a torpedo that struck the vessel as it was returning to Iran, marking one of the rare instances since the Second World War in which a submarine destroyed a surface warship.

Prime Minister Anthony Albanese confirmed the Australians were participating in a long standing training arrangement that embeds defence personnel within allied forces. He stated that no Australian took part in offensive action and that embedded personnel operate in accordance with Australian law and policy. A source told an Australian news outlet that the sailors were deliberately kept away from the offensive operation.

The Iranian vessel sent a distress call about seventy five kilometres off Galle before sinking. Footage showed a large explosion beneath the stern, and rescue crews later found oil slicks and life rafts. Iran's foreign minister condemned the strike as an atrocity and warned of consequences, while a former British naval chief described the घटना as escalating a regional conflict into a global war.