A company paid about $440 million a year to run the Manus Island detention centre is allowing drunken staff to misbehave, the Papua New Guinea government says, ordering its own officials to intervene after Australian workers allegedly sexually assaulted a local female employee. 
Prime Minister Peter O'Neill has announced he will impose a "zero tolerance" approach to alcohol and drugs at the centre, including regular substance testing, to ensure an alcohol ban there is properly enforced.
He said the company in charge of contract workers had not "maintained discipline" and PNG's chief migration officer would impose stricter controls.
The Australian government pays Transfield Services about $440 million a year to operate the Manus Island centre, and has a separate contract for an asylum seeker facility at Nauru.
Transfield Services subcontracts Wilson Security to maintain safety and order at both centres.
In mid-  July, three Australian Wilson Security guards were allegedly found naked with a woman who claimed she had been drugged and sexually assaulted. The guards are now back in Australia - a move that angered PNG police who were investigating the incident.
Mr O'Neill said he was awaiting a report on the allegations but "alcohol played a part in what did transpire".
"This is not the first time we have heard of inappropriate expatriate behaviour as a result of alcohol consumption, and this has to stop," he said.
"The [centre] is a dry facility and staff are not permitted to consume alcohol."
He said staff found to have consumed alcohol or taken drugs would be dismissed.
"The foreign workers at the [centre] have signed agreements as part of their employment that come with strict conditions," Mr O'Neill said, adding they were paid generously for their work.
Many were former military personnel who "should have the discipline not to need to drink while they are away on a posting".
Mr O'Neill's strong comments come amid anger among Manus Island residents about the alleged sexual assault of the local woman.
Manus police had threatened to arrest all Australian managers at the centre if Australian authorities did not return the accused men. However, the deadline passed last Thursday and it appeared no arrests were made.
The Department of Immigration and Border Protection and Transfield Services have been contacted for comment.
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