During the staff meeting on January 30, Mr McCaffery told staff that G4S had repeatedly raised with the department the need to give asylum seekers some certainty about when their claims for refugee status would be assessed. Mr McCaffery reported that a request made the previous day for immigration officials to address the detainees had been rejected. He also reported that he had been told by PNG's chief migration officer that no refugee status determinations (RSDs) would take place for the foreseeable future because he had "no money in his budget to pay for RSD officers". Another senior official told the meeting three unaccompanied minors had been identified that day. All were 17 and were being held in an area called the Green Zone apart from the centre's four compounds until it was decided whether they would be transferred elsewhere. A spokesman for Mr Morrison said that his statement about processing was ''based on the understanding of the situation at the time of making the statement''. He added that Australia met the cost of processing.

The Immigration Department was not aware of any unaccompanied minors in the centre now or around the time of the violence, Mr Morrison's spokesman said. The meeting outlined fears of a major and violent incident more than two weeks before it occurred and the steps taken to minimise the risks. It sheds new light on the inability of those employed at the centre to deal with a host of problems, from the depression of detainees fuelled by uncertainty, to the lack of basic amenities. The recording raises a host of issues that were not fully explored in the departmental probe by Robert Cornall and are likely to be pursued in a Senate inquiry starting on Tuesday that will see Mr McCaffery and several other G4S staff give evidence. These include the assertion that the protest leaders were not only from Iran, and included detainees from Iraq and Lebanon, and the problems posed by a detainee population comprised only of men. At one point an unidentified official complains of the lack of shade from the intense sunlight, saying: "While they're getting their brains cooked from the outside, they're not thinking straight."

Another official recalls telling asylum seekers who were losing patience after being in the centre several months: "Don't take this the wrong way, but there's people in detention centres on Christmas Island and so forth that have been there over three years. Youse are just babies. You've just got here!" Less than three weeks before the first night of violence, Mr McCaffery opens the meeting by warning those present that the situation is deteriorating, sparking fears of a repeat of riots on Christmas Island and Nauru. He then announces that a policy of much less tolerance will be introduced, saying detainees will be told that they will be subject to PNG's "draconian" assembly laws that require advance warning of any protest, identification of leaders and when the protest will begin and end. "We're spent a lot of time being accommodating and that has worked, allowing the transferees to express their opinions and to communicate with each other and with us," he says. "Regardless of how they feel, tomorrow we are going to start reasserting control in the compound."

Mr McCaffery is constantly reminded of logistical and other challenges, including the inability to remove alleged protest leaders from others, the lack of information and the lack of radios and other basic equipment. "It is what it is, mate," he replies. "We're at the end of a very long supply chain which constantly fails." The recording also reveals Mr McCaffery's empathy for the asylum seekers and his intention that they be treated by human beings. Among others who will appear before the inquiry is whistleblower Steve Kilburn, who says in a submission, that Manus Island is not a suitable location for the Regional Processing Centre and "we cannot guarantee the safety of the transferees housed in this facility". Greens Senator Sarah Hanson-Young, who has listened to the recording, says it shows that, despite Mr Morrison's claims that asylum applications were being processed, "that simply wasn't true".

Loading Senator Hanson-Young said serious questions about Australia's duty of care and the government's role in the brewing tensions had not been addressed by the Cornall review and would be pursued by the Senate inquiry. Follow us on Twitter