A boatload of 89 asylum-seekers has been intercepted off the coast of northern Australia, a day after the Australian government announced that boatpeople will no longer be resettled in the country.

Tony Burke, the immigration minister, said on Saturday that the group - "entirely or almost entirely" Iranians - would be offered the choice of either pressing ahead with an asylum claim and being sent to Papua New Guinea, or transfer to another country.

Earlier, a protest at an Australian-run immigration detention camp in Nauru turned violent, with some of the asylum seekers injured, officials and witnesses said.

Buildings were torched as hundreds of asylum-seekers escaped detention during riots at the refugee facility, witnesses said on Saturday.

The riots on Friday night saw detainees take control of the immigration processing centre on the remote Pacific island of Nauru and arm themselves with knives and steel bars.

As of midnight Australia's immigration department said all the asylum-seekers had been accounted for and order had been restored.

An immigration spokeswoman said that most of the major buildings including the accommodation blocks, medical centre, dining hall and offices had been destroyed during the protest, which involved about 150 detainees.

Four detainees had been hospitalised with minor injuries and no staff were hurt, she added.

Locals support police

Nearly half of the facility's 545 asylum-seekers escaped and a number of buildings were set alight, according to local photographer Clint Deidenang.

"Today was history. The biggest riot ever to be staged on Nauru soil. The most violence I've seen. Amazing support from local(s) to the police," Deidenang told AFP.

The asylum-seekers abandoned their four-hour protest after a huge group of locals descended on the centre armed with pipes and machetes to help authorities contain the violence in response to a government call for assistance, he added.

"The ringleaders apprehended at the site will be questioned by police about allegations of property damage, destruction of property and riotous behaviour," she said.

Australian Prime Minister Kevin Rudd hopes the hardline plan will boost his fortunes in an election year by stemming the flow of boat arrivals, which have exceeded 15,000 so far this year.