Four refugee activists scaled the Sydney Opera House on Thursday morning and unfurled a banner that read "Australia world leader in cruelty" to protest what the UN has called a "humanitarian crisis" unfolding on Papua New Guinea's Manus Island.
Around 600 refugees and asylum seekers have been living without food, water or electricity for more than a week inside the Manus refugee detention facility, which was shut down by Australia last week.
"The Sydney Opera House is an international icon of Australia. But increasingly our country is becoming internationally recognised for our human rights abuse to refugees," Lily Matchett, a spokeswoman for WACA, the refugee activist group that organised the protest, told DPA.
The Australian government "must end offshore detention and bring the refugees here immediately," she said.
Four climbers, including two abseilers who reached the top of one of the iconic building's sails to unfurl the banner, were arrested, Matchett said. 
A fifth person was arrested in the vicinity of the building.
"Right now men on Manus Island are starving, stricken with thirst, and suffering enormous torment. This is the result of incompetence, bigotry, and a sick political process," she said.
The refugees have refused to move to temporary accommodation - some of which is only partially constructed - near the island's main town of Lorengau due to fears of being attacked by locals.
Meanwhile, PNG's Prime Minister Peter O'Neill issued a statement late on Wednesday threatening to arrest detainees for "the well-being of both the refugees and non-refugees".
"Those involved in disruption have been identified and appropriate means will be used to apprehend individuals who are causing unnecessary anxiety and violence," O'Neill said.
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