The federal government says it will not be pressured by refugees refusing to leave the decommissioned Manus Island detention centre, as PNG police removed 50 men barricaded inside to new facilities.
It came as Kurdish refugee and journalist Behrouz Boochani was released by PNG authorities, after being detained.
Mr Boochani tweeted following his release, saying he had been handcuffed for more than two hours.
A picture circulated by refugees inside the former detention centre showing Mr Boochani being led away by officers in military uniform.
He was taken away during a police raid on the camp.
Mr Boochani had been acting as an unofficial spokesman for hundreds of men holed up in a closed Australian detention centre.
"We have confirmed that he has been taken away," Shen Narayanasamy of Australian activist group GetUp told AFP, speaking of Boochani.
"We are very concerned about his welfare... He's become a voice on behalf of the men detained in this camp now for four years.
"The police station and the jail inside Manus are places in which it's very difficult to get information."
Boochani had been regularly tweeting and talking to journalists by phone about the conditions in the camp.
In a statement Papua New Guinea's Police Commissioner Gari Baki denied that Mr Boochani had been arrrested and charged and said he was simply "escorted out" of the centre.
"He was stirring up trouble and telling the other refugees not to move out of the centre," Mr Baki said.
"Everybody has been jumping up and down about the treatment of the refugees which is nothing but the best so far."
Narayanasamy said his phone had been taken away from him, and other refugees were worried police now had a policy of arresting people who had spoken to media outlets.
Another detainee, Sudanese refugee Abdul Aziz Adam, tweeted: "Please don't... text Behrouz right now he has been arrested by the police few minutes ago."
Boochani gained international recognition for shooting footage on a smartphone inside the Manus camp for a film that was shown at the London Film Festival in October.
Global rights group Amnesty International called for his immediate release, saying that it "seems this is a deliberate attempt to isolate human rights activists from the wider group".
SBS News understands two other men were also taken into custody during the raid.
Immigration Minister Peter Dutton has confirmed the arrests.
"My understanding is a small number of people have been arrested, including the individual (Boochani)," he told Sky News.
The Australian union for journalists said the arrest of Mr Boochani was an attack on press freedom.
The MEAA said the Kurdish refugee appeared to have been deliberately targeted because of his reports inside the centre.
“If, as the case appears to be, he has been targeted and arrested because of his profile and his role as a journalist in an attempt to silence him, this is an egregious attack on press freedom that cannot be let stand," Union CEO Paul Murphy said.
“We will also be bringing this to the immediate attention of the International Federation of Journalists, the global body for journalists.”
Dozens of men moved to new facilities
PNG police entered the centre Thursday morning in an attempt to remove asylum seekers who have refused to leave.

Picture of Kurdish refugee Behrouz Boochani arrested by PNG authorities. Source: Supplied/SBS World News
Multiple men at the centre have reported on social media that they were told to move, with some claiming the police officers were acting aggressively and destroying property.
PNG police later confirmed that 50 men were removed from the centre, but not against their will.
"36 non-refugees and 13 refugees left voluntarily...Kurdish journalist Behrouz Boochani was escorted out," Police Commissioner Gari Baki said in a statement.
The police action follows several attempts over the past three weeks to get the remaining asylum seekers, now estimated at about 328, to leave the centre and move to new facilities which the Australian government has constructed elsewhere on the island.
'We won't be pressured': PM
Prime Minister Malcolm Turnbull said the men should move to the new transit facilities and respect the laws of PNG.
“They think this is some way they can pressure the Australian government to let them come to Australia. Well, we will not be pressured,” he said.
The government would not “outsource” its migration policy to people smugglers, he added.
“The people on Manus should go to the places - alternative places of safety with all of the facilities they need.
“They should do so peacefully and they should do so in accordance with the lawful directions of Papua New Guinea.”
'The tenant who won't move out of the house'
Earlier, Mr Dutton said the Turnbull government was keen for people to move out of the processing centre.
"I think it's outrageous that people are still there and they have trashed the facility, they're living in squalor," he told 2GB radio.
"The Australian taxpayers have paid about $10 million for a new facility and we want people to move."
Mr Dutton again reiterated the men will never be coming to Australia.
"It's like the tenant that won't move out of the house when you build a new house for them to move into," he said.
Mr Dutton blamed refugee advocates for pushing the refugees to stay in an effort to get media coverage but repeated his assertion that none of the refugees would ever be permitted to come to Australia.
Australian Federal Police 'not involved'
The Australian Federal Police confirmed they have one liaison officer on the island who "works in an advisory and mentoring capacity to the RPNGC on policing matters".
"The AFP has no member within the former Manus Regional Processing Centre and no involvement in today's actions," a spokesman said, adding the "response... is led by PNG authorities."
Video uploaded by Sudanese refugee Abdul Aziz Adam showed a group of officials in yellow shirts with a police officer believed to be Manus Provincial Police Commander, Chief Inspector David Yapu, issuing a directive over a megaphone to the men barricaded inside.
"This place will be under the... PNG Defence force," he said.
"It is their military base, and you're staying here … would be seen as illegal and unlawful.
"All the services have been cut off and I sympathise for that, and there is no power, there is no water."
Refugee Samad Abdul told SBS News there was a "huge" number of police and immigration officials, allegedly "destroying everything".
"They gave us only one hour and said anything can happen anytime and we will be not responsible," he said.
Commissioner Baki said there are 10 Immigration officials and 50 policemen on Manus trying to manage more than 600 refugees whilst at the same time attend to ongoing law and order issues on the island province.
'We don't want to go. We will die here!'
Before he was taken by authorities, Mr Boochani alleged the officers were destroying shelters and water tanks.
"Saying 'move, move'. Too much tension and too scary," he tweeted.
Another video uploaded by refugees on Thursday morning shows the men shouting amid a scrum with immigration officials: "We don't want to go! We will die here!"
Refugee Zazai Walid tweeted photographs of refugees' property he said was destroyed by the PNG officers.
Australian government criticised
Greens MPs and human rights groups have condemned the Australian government for its role in the crisis, while former Australians of the Year have written an open letter to Prime Minister Malcolm Turnbull and opposition leader Bill Shorten urging them to address the "human disaster" unfolding on Manus Island.
Human Rights Watch Australia Director repeated the organisation's criticism of Australia over the standoff, posting a video on Twitter of refugees reviving a man who had fainted.
"Australia, you are trashing your reputation by allowing this PNG clearance operation against men in your care," she wrote.
Really distressing scenes as refugees revive a man who fainted at #Manus main center. Australia, you are trashing your reputation by allowing this PNG clearance operation against men in your care. pic.twitter.com/3C8MSkmk97 — Elaine Pearson (@PearsonElaine) November 22, 2017
- With AFP