The Greens and refugee advocates called for Mr Morrison's resignation after he admitted late on Saturday evening that most of the violence - including the death of 23-year-old Iranian man Reza Berati - had likely happened inside the centre, not outside, as he'd first claimed. His admission raises serious questions about the management of the centre by private security firm G4S and doubts about the flow of information to the minister, who made his correction five days after the incident. Nevertheless, Mr Abbott said his immigration minister was doing a ''sterling'' job in stopping the boats and had used the best information available to him at the time he made his original statements. ''You don't want a wimp running border protection,'' he said. ''You want someone who is strong, who is decent and Scott Morrison is both strong and decent.'' Mr Abbott added there had been ''very little damage'' to the centre itself in the riot. ''Now, obviously you would rather not have riots, but if there are riots they have to be dealt with and this one was dealt with,'' he said.

Opposition immigration spokesman Richard Marles said on Monday that he was ''appalled'' by the Prime Minister's ''wimp'' comment. ''These are comments which are more suited to a school yard than a statesman,'' Mr Marles told ABC radio. ''This is not a macho contest,'' he added. ''When I hear the Prime Minister, my initial reaction is he just needs to grow up.'' Opposition Leader Bill Shorten said on Monday that Mr Abbott's defence of Mr Morrison for not being a ''wimp'' was irrelevant. ''We don't need people who are wimps or not wimps, we need people who know what they’re doing,'' he told ABC radio in Melbourne.

Mr Morrison's statement underscored the fact that the spotlight is now on G4S staff, who are responsible for security inside the centre, while reiterating that detainees were putting themselves at risk by engaging in ''riotous and aggressive behaviour''. He added that ''in such circumstances, service providers [referring to G4S] must conduct themselves lawfully and consistent with the service standards set out in their contract''. Mr Morrison said last week that he could guarantee the safety of detainees if they ''remain in the centre and act co-operatively''. He stood by that remark yesterday, though he was unable to say whether Mr Berati or any of the wounded detainees had been rioting or behaving aggressively. Asked whether he had confidence in G4S's handling of the incident, Mr Morrison said: ''Well I am going to wait for the review before I draw any conclusions on that front.''

Mr Morrison said that he'd learnt only on Saturday that he'd been wrong in claiming most of the violence happened outside the centre. In a statement on Sunday, G4S stepped back from its previous assertions that its staff had acted professionally. ''G4S will take the strongest disciplinary action against any employee found to have been involved in any wrongdoing against any person in our care, the laws of PNG and our strict code of ethics,'' it said. Local workers have been kept out of the centre in recent days, with only foreign employees managing the workload. A worker told Fairfax Media that the situation highlighted the tension and fear now between asylum-seekers and locals. David Manne, the refugee lawyer who scuttled the Gillard government's Malaysia Solution, said the government was in breach of the UN Refugee Convention and other obligations under international law.

''Australia's core obligation to asylum seekers is to protect them from harm - an obligation which cannot be met by sending them to Papua New Guinea,'' he said. ''The many people seeking protection in Australia are fleeing from the same forms of inhumanity unfolding on Manus Island. [These include] arbitrary incarceration, brutal harm and death.'' One Liberal MP, who sits on the right-wing flank of the party, said it was not good enough that it took Mr Morrison the best part of a week to confirm to the Australian public a fact as central as whether the violence occurred inside or outside the detention centre. ''I don't know when Morrison found out,'' the MP said. ''But something like this, it should not take the best part of a week to inform the public.'' Manus Island member of Parliament Ron Knight said the violence could have been prevented had G4S been more open about what was going on inside the centre.

He said he'd sent two of his staff to the centre last Monday afternoon - hours before the riot erupted - to investigate but they had been turned away by an Australian security guard. ''If they'd told us what was happening, we could have had - in two or three hours - two more police squads in the base, and that would have been a serious deterrent,'' he said. Mr Marles said on Sunday that Mr Morrison's admission of giving wrong information raised ''enormous questions'' about his ability to manage the issue. ''This is a man who has no idea what's going on at Manus Island,'' he said. Greens Senator Sarah Hanson-Young said Mr Morrison had to resign. ''As a country we failed those who asked us to keep them safe,'' she said.

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