A boatload of asylum-seekers picked up by a Singaporean merchant vessel after a distress call were on Thursday accused of acting like pirates after forcing the captain to take them to Australia.
The Singapore-flagged MV Parsifal picked up the 67 asylum-seekers from a people-smuggling ship off the Indonesian island of Java on Monday in response to a distress call relayed by Australian authorities.
It intended to continue on to Singapore with the group but Canberra's Home Affairs Minister Jason Clare said they became "very aggressive" when learning of the plan and insisted he take them to Australia's Christmas Island.
"The master of the ship made the decision to turn the vessel around and head to Christmas Island," Clare told ABC radio.
"The captain rang the Australian Maritime Safety Authority to tell them of his intentions, and he made the point that he was concerned for his crew's safety."
Opposition immigration spokesman Scott Morrison said the group should be investigated by Australian police for piracy, describing their behaviour as "outrageous".
"For the vessel to have been turned around allegedly under threat of violence, to go completely in the opposite direction... is an outrageous act to be committed," Morrison told reporters.
"They should be investigated for potential crimes of piracy."
Prime Minister Julia Gillard conceded that if there had been "a breach of any relevant laws then of course it has to be properly investigated", but said the "time for political argy-bargy" on the boatpeople issue had passed.
Clare said the group could be among the first sent to remote Nauru or Papua New Guinea's Manus Island under a punitive new policy to detain asylum-seekers offshore currently being debated in the upper house of parliament.
"There's no advantage in that sort of behaviour, because these people now face the prospect of going to Nauru," he said.
If passed as expected by the Senate the new measures will let Australia send asylum-seekers who arrive by boat to remote Pacific outposts for processing without a time limit on their detention.
Canberra hopes the approach will act as a deterrent to the record tide of people-smuggling boats from Indonesia and Sri Lanka.
The new laws represent a return to the harsh refugee policies of the former conservative government, which were rolled back by Gillard's centre-left Labor when it won power in 2007.