CANBERRA, Australia -- Papua New Guinea authorities on Thursday removed dozens of asylum seekers and ratcheted up pressure on more than 300 others to abandon a decommissioned immigration camp, where refugees reported their shelters, beds and other belongings have been destroyed.

Police Commissioner Gari Baki said 50 police and immigration officials entered the Manus Island camp Thursday morning and "peacefully relocated" 50 asylum seekers among the 378 men to alternate accommodations in the nearby town of Lorengau.

Water, power and food supplies to the Manus camp ended when it officially closed on Oct. 31, based on the Papua New Guinea Supreme Court's ruling last year that Australia's policy of housing asylum seekers there was unconstitutional. But asylum seekers fear for their safety in Lorengau because of threats from local residents.

Australia pays Papua New Guinea, its nearest neighbour, and the tiny Pacific nation of Nauru to hold thousands of asylum seekers from Africa, the Middle East and Asia who have attempted to reach Australian shores by boat since mid-2013.

Shen Narayanasamy, a human rights campaigner for the activist group GetUp!, said some of those bused from the camp on Thursday reported being forced to leave.

Baki said in a statement all had "left voluntarily" except for Iranian refugee Behrouz Boochan, a journalist who used social media to report on disturbing conditions on Manus.

Australian Immigration and Border Protection Minister Peter Dutton told Sky News television that Boochan was among "a small number of people ... arrested."

But Baki said Boochan was neither arrested nor charged.

"He was stirring up trouble and telling the other refugees not to move out of the centre so police and officers ... simply escorted him out," Baki said. "I am glad that this relocation exercise was done peacefully and without use of force."

Boochan had earlier tweeted from the camp: "They are destroying everything. Shelters, tanks, beds and all of our belongings."

Police Chief Superintendent Dominic Kakas denied reports that authorities destroyed asylum seekers' property in an effort to persuade them to leave.

Amnesty International cited reports of immigration officials entering the camp armed with sticks and knives.

"The risks of serious injury if the authorities use force now is completely foreseeable," the London-based rights group's researcher, Kate Schuetze, said in a statement.

Authorities have previously made conditions tougher in the camp by emptying drinking water tanks and removing shelters. Deadlines to abandon the camp have passed without authorities taking action.

Australia will not settle any refugees who try to arrive by boat -- a policy that the government says dissuades asylum seekers from attempting the dangerous ocean crossing from Indonesia. It has also prevented boats from reaching Australia since July 2014 by using the Australian navy to turn boats back.

The United States has agreed to resettle up to 1,250 of the refugees under a deal struck by former President Barack Obama's administration that President Donald Trump has reluctantly decided to honour. So far, only 54 have been accepted by the United States.

Prime Minister Malcolm Turnbull dismissed asylum seekers' fears for their safety in Lorengau, accusing them of trying to pressure Australia into resettling them by refusing to move from Manus.

"They think that ... in some way they can pressure the Australian government to let them come to Australia. Well, we will not be pressured. We will not outsource our migration policy to people smugglers," Turnbull told reporters.

"People on Manus should go to the alternative places of safety with all the facilities they need, they should do so peacefully and they should do so in accordance with the legal directions of Papua New Guinea," he added.