SYDNEY: Thirty-five asylum-seekers broke out of an Australian immigration detention on Papua New Guinea's Manus Island and several were injured, officials said Monday, as tensions mount about their fate under hardline policies.

Australian Immigration Minister Scott Morrison said the asylum-seekers escaped Sunday evening but were quickly rounded up by private security contractors at the facility, one of two remote Pacific camps used in Canberra's punitive off-shore detention policy.

Under the scheme, aimed at deterring people-smugglers, any asylum-seeker arriving by boat or intercepted at sea is transferred to Manus or Nauru for processing and permanent resettlement outside Australia.

Morrison said power poles and fences were toppled during the fracas, and bunk beds smashed to fashion makeshift weapons, but no buildings were destroyed.

Eight detainees were arrested over the disturbance, and Morrison said 19 went to the medical centre for treatment, “none of whom were exhibiting life-threatening conditions”.

“As at this morning, five of those transferees remained at the clinic. A number of G4S (security contractor) staff also sustained minor injuries,” Morrison told reporters.

He said he did not yet have a full report about the medical conditions of those who were treated.

Refugee activist Ian Rintoul said a number of the asylum-seekers had suffered broken hands and baton injuries, adding that one “has 70 stitches in his head”, indicating a “use of force last night out of all proportion”.

Rintoul said detainees now feared vigilante reprisals from islanders who oppose the Australian facility, with some inside the camp telling him locals had armed themselves with machetes, knives and guns.

“The imposition of the detention centre on Manus Island has created local tensions from the very start. The lack of transparency about resettlement has added to the tensions,” he said.

The breakout followed a tense meeting at the centre between detainees and officials from Papua New Guinea's immigration and citizenship authority (ISCA) to discuss their fate if they were found to have a genuine refugee claim.

Morrison said detainees “became agitated and commenced chanting” after they were informed they would be resettled in PNG and “a third country option will not be offered”.

They were also told that “that neither the PNG or the Australian governments will be acting on behalf of the transferees in seeking alternative settlement countries to PNG”, added Morrison.

Though security staff used “personal protection gear”, Morrison said “no batons or other weapons were in situ”.

He would not clarify what the gear was and whether it included capsicum spray.

He described resettlement as a “challenge” — the details of which were yet to be hammered out with Papua New Guinea's government — and suggested that the Manus facility could become a permanent home for some of the 1,340 currently housed there.

“It's not restricted to being a temporary accommodation,” he said.

“If people are resettled (in PNG) then that's a possibility.”

The United Nations refugee agency has condemned the Manus and Nauru camps as “harsh” facilities that “impact very profoundly on the men, women and children housed there”.

Prime Minister Tony Abbott said people in the camps were treated humanely, but “if you come to Australia illegally by boat, this is, I'm afraid, what happens to you”.

“It's impossible not to feel sorry for people who want a better life and who are living in a horrible country and I guess it's good that they think Australia is a beacon,” he said.

“We are a beacon — a beacon of freedom and decency and generosity — but we cannot allow people to take advantage of our generosity in this way.”