More than 700 foreign IS family members escaped a Syrian camp during a Turkish offensive after IS fighters fled a prison – as the UN said more than 130,000 Kurds have been displaced.
The terror group said it was behind a car bombing on Friday in Qamishli, the largest city in Kurdish-held northern Syria, which allowed some of the thousands of IS fighters held in Syria to escape.
On Sunday, the Kurdish-led authorities said 785 foreigners affiliated with IS escaped the Ain Issa camp after it was shelled by Turkish forces and their allies, the UK-based Syrian Observatory for Human Rights (SOHR) said.
The Kurdish-led Syrian Defence Force (SDF), allied with the US and the UK, was left to guard the prisons holding 11,000 IS fighters, and detention centres with 70,000 IS family members after US forces were pulled out of the region this week.
Their escape over the weekend came as the UN said more than 130,000 people have been displaced from the region in the four days since Turkish forces and their Syrian rebel allies started the offensive.
More than 30,000 people were forced out of their homes on Sunday after Turkey seized large parts of the town of Suluk, following the capture of the border towns of Tel Abyad and Ras al Ain.
Turkey said it plans to continue the offensive for a further nine days.
The SOHR said 104 Kurdish-led fighters have been killed in the fighting, while 49 Turkey-backed Syrian rebels have died and 30 civilians have been killed in Syria.
In Turkey, 18 civilians have been killed in cross-border bombardment, Turkish media and officials say.
As Turkish forces advanced into the area, video released by Kurdish supporters, seen by Sky News, showed two prisoners being executed by the side of a road by Turkish-backed Syrian rebels.
The unverified images showed the rebels stamping on a Kurdish flag and using a rifle butt to deface a picture of their leader.
Sky News foreign affairs editor Deborah Haynes, who is on the Turkey-Syria border, said: “If these images are found to be true, they show an undisciplined force.
“It is further evidence of the real ethnic dangers of releasing this in a country that is so unstable.
“It raises questions of ethnic cleansing – that Kurdish families could be indiscriminately targeted.”
Turkey is facing fierce international opposition after its president, Recep Tayyip Erdogan, launched the offensive when US president Donald Trump announced he was pulling US troops out of northern Syria.
Mr Trump has defended his decision, which left the SDF at risk because Turkey views them as a terrorist threat due to their link to the Syrian Kurdish People’s Protection Units (YPG), deemed a terror group by Turkey.
At a rally on Saturday Mr Trump said the US cannot fight “endless wars” and announced the it has sent $ 50m (£39.5m) in emergency aid for Syria to support Christians and other religious minorities there.
The US has threatened Turkey with sanctions unless it calls off the incursion.
In the UK, Boris Johnson expressed “grave concern” about the offensive as he urged President Erdogan to end the operation during a phone call on Saturday evening.
France and Germany announced they would stop selling weapons to Turkey that could be used in the conflict.
The humanitarian situation has escalated dramatically since Turkey launched the offensive, but the International Rescue Committee warned it could get “more dire” as Turkey advances further into the region.
Misty Buswell, IRC’s policy director, told Sky News: “These towns, Ras al Ain and Tal Abyad, have become basically empty of people.
“Everyone has left, they’re moving into areas that are already overstretched and under Islamic State for four years previous to this.
“People are really suffering and now they’re seeing mass displacement into areas that were just beginning to recover.”
She added hospitals in the most impacted areas have been forced to close and those that remain open are becoming overwhelmed.
A water station which provides water for drinking and washing to up to 400,000 people in the area was hit by Turkish government forces, prompting fears of disease spreading as people resort to unclean sources.
Mr Erdogan says the military action is necessary for national security, saying on Saturday: “We will never stop this step we have taken… We will not stop it no matter what anyone says.”