Turkey has pledged to take custody of Islamic State prisoners within the buffer zone its forces are trying to create in northern Syria, but there are fears among human rights observers and others that a humanitarian catastrophe could follow.

The country's foreign minister made clear, on the second day of the incursion, Turkey is "not responsible" for camps outside of its area of operation.

There are at least four detention centres within the contested territory where there are signs Syrian Democratic Forces (SDF), led by the Kurdish YPG, have begun to reduce security, moving fighters away from guard duty and toward the fighting with Turkey..

Truckloads of soldiers reportedly left al-Hawl, a displacement centre close to the Iraqi border, on Monday for an unknown destination, according to witnesses who spoke to Human Rights Watch.

Letta Tayler, the organization's senior researcher in terrorism and counterterrorism, has been in touch with women in the camp, where the already squalid conditions are said to be deteriorating.

Mood is tense

The mood in the camp is very tense, she said.

"Some women have said that the SDF, the Kurdish-led forces controlling the camp, have told them that the Turks will come in here and shoot you," said Tayler. "But it's hard to know if this was what one guard said to one woman. It spread like wildfire, like many rumours."

In this file picture taken on Friday, July 21, 2017, Kurdish soldiers from the Anti-Terrorism Units, in the background, stand in front a blindfolded Turkish suspected Islamic State member, Onur, at a security center, in Kobani, Syria. (Hussein Malla/Associated Press)

Canada and the rest of the international community have a responsibility to prevent a humanitarian disaster and there should be a co-ordinated effort to move the women and children away from the fighting, she said.

"Let's not forget that the vast majority of inhabitants of these locked camps are young children; children do not choose their parents," she said. "They did not choose to live under ISIS and they should not be punished for the crimes of their parents."

The former commander of Canada's special forces said it is a precarious scenario and may not be as painless as the Turks have suggested.

"I'm trying to imagine how a handover [a prisoner camp] would occur between two belligerent forces," said retired major-general Denis Thompson, who last commanded the multinational peacekeeping force in the Sinai, where ISIS was active.

"It's almost as if you would find yourself at the end of World War Two where Allies drive up to a camp and they're greeted by the German guards and the German guards calmly hand over the camp to them. I just can't imagine that scenario rolling out that way."

Fighters could be freed

Earlier this week, defence experts warned that reduced security at the camps, which have been under Kurdish control since the fall of ISIS, could lead to a prison break — or even the release of thousands of extremists and their families.

Thompson, who also led Canada's counter-insurgency mission in Afghanistan in 2008-09, said newly freed ISIS fighters could rejoin the conflict in Syria and Iraq, but they would have to be rearmed and re-equipped.

"If these prisons and detention camps are vacated and those fighters are loose, well, then they can become part of the security problem going forward," said Thompson, who added that problem would be owned by Turkey.

The United States has already taken custody of two high-profile former ISIS fighters.

Kamran Bokhari, the founding director of the Washington-based Center for Global Policy, said the Turkish offensive to dislodge the Kurds from the border region of Syria is a high-risk venture in the sense that the Trump administration has put a lot of faith in quick, successful resolution of the operation and that includes the handling of ISIS prisoners and their families.

"The United States has said, you know, this is your problem," said Bokhari. "You have accepted the responsibility. You have taken the job. Now, you need to deal with this. Now it's up to the Turks to say, OK, we'll sort them out. Where do they come from? What countries do they hail from? Negotiate with those countries for their return."

Canada and many western European countries have refused to take back their citizens who left to join the caliphate. There are approximately 33 Canadians — men, women and children — detained in Syria who have had ISIS connections in one way or another.

Members of the People's Protection Units (YPG) are shown in a Sept. 11, 2018 file photo. Turkey has said it wants to push the YPG back from the Turkish-Syrian border. (Delil Souleiman/AFP/Getty Images)

The Turkish embassy in Ottawa released a statement Thursday that did not address the question of ISIS prisoners, but emphasized that every effort is being made to spare civilian lives.

It said the operation was launched to "eliminate terrorist elements" along the border. Turkey has fought a long-running campaign against Kurdish militants in the region, a conflict which it blames for the deaths of as many as 40,000 of its citizens.

Stakes high for Turkey

Steve Saideman, director of the Canadian Defence and Security Network and a professor at Carleton University, said beyond the question of handing detainees, the stakes for Turkey within NATO are extraordinarily high.

"There's a lot of discussion about kicking Turkey out of NATO," Saideman "I don't think that's gonna happen, because there's not really procedures within NATO to do that, but there's been this will."

NATO's secretary general is due to visit Ankara on Friday.

"Turkey expanding this buffer zone might seem like a good short-term solution, but is not resolving the problems that Turkey faces," said Saideman. "They still have their own Kurdish minority that is upset."

The worst damage, he said, is to "American credibility, which is now being questioned even more" by not only nations, but the proxy forces it has used to fight its wars.

The perception is "the United States has been utterly unreliable because Donald Trump has a conversation with a leader of a country [and] flips his policy immediately."