Australia's Immigration Minister, Tony Burke, will visit Papua New Guinea's Manus Island this week to investigate claims by a former security guard that asylum-seekers held there have been tortured and raped by fellow detainees, with the full knowledge of staff.
Rod St George, who quit as head of occupational health and safety at the Australian-run processing centre in April, told the SBS Dateline programme acts of self-harm and attempted suicide were occurring "almost daily".
He also said detainees were stockpiling weapons and were "quite open that there will come a time where they will break out and people will be killed".
The explosive claims by St George, who said he had "never seen human beings so destitute, so helpless and so hopeless before", came just days after Prime Minister Kevin Rudd said all asylum-seekers arriving by boat would be processed in PNG and - if their refugee claims are deemed genuine - resettled there.
As part of the new, hardline policy, the camp on Manus - about 300km north of the PNG mainland - is to be greatly expanded, to accommodate about 3000 people.