We will not be pressured by Manus Island refugees - Australian PM

Australian Prime Minister Malcolm Turnbull says he won't be pressured by refugees refusing to leave the decommissioned detention centre at Manus Island in Papua New Guinea.

Local police moved into the facility on Thursday in an attempt to move the 400 refugees still holed up there.

Power, food and water supplies were cut to the Australian-run centre but the refugees have refused to relocate to new accommodation facilities nearby.  

"They think this is some way they can pressure the Australian government to let them come to Australia," Mr Turnbull said after a number of refugees spoke out after police moved into the facility.

"We will not be pressured."

There were chaotic scenes at the Manus Island centre on Thursday as authorities took back control of the centre, telling the refugees they must leave.

Refugees say police and guards have thrown rocks and punched people in the legs and face, and Newshub has obtained unverified videos from inside the centre showing the chaos.

Sudanese refugee Abdul Aziz Adam locked himself in a toilet to speak to Newshub on the phone. He says he witnessed two people being attacked.

"They are throwing rocks at the people, they have got baton sticks in their hands, and they are spitting, swearing, abusing people," he says.

"They kicked those guys in their feet and they step on their feet and one of them say something he say why you do that you are not a human being he punched him in the face straight away."

Mr Adam says police and guards ransacked the facility, destroying beds, throwing away belongings and water.

"I'm so terrified and I'm scared," he says.

Refugees Newshub spoke to say about 100 police, immigration and military staff were involved.

However, PNG police spokesman Dominic Kakas told the ABC in Australia that 10 immigration officials and about 40 police moved into the centre.

"Immigration officials went in and explained to them that they had no legal standing … voluntarily they packed their bags and moved across (to the new facility)," he said.

"Police and immigration officials are still in the centre and they are basically talking to (the refugees and asylum seekers) and trying to reason with them."

The event is the most forceful effort yet to move the men to a new $10 million accommodation facility. They're refusing to leave as they say the new centre lacks proper security and medical facilities, something the Australian government denies.

New Zealand has offered to take 150 of the refugees but this hasn't been taken up by Australia.

A lawyer acting for the refugees, Hobart-based Greg Barns, says New Zealand should ignore Australian Immigration Minister Peter Dutton and deal with Papua New Guinea directly

"He treats Jacinda Ardern with contempt, it's time New Zealand stood up," he argues.

Several media are reporting that a small number of refugees were arrested on Thursday, including Iranian refugee and journalist Behrouz Boochani who has since been released.