Akcakale, Turkey - Turkish forces approached a key Kurdish-held town in northern Syria on Sunday, setting off clashes that allowed hundreds of Daesh supporters to escape from a camp for displaced people near a US-led coalition base.

The United Nations meanwhile said more than 130,000 Syrians have fled since the operation began five days ago. The fighting reached the main highway that runs between Hassakeh, a major town and logistical hub, and Ain Eissa, the administrative centre of the Kurdish-held areas.

The camp in Ain Eissa, some 35km south of the border, is home to some 12,000 people, including 1,000 wives and widows of Daesh fighters and their children. The Kurdish-led administration in northern Syria said in a statement that 950 IS supporters escaped after attacking guards and storming the gates. It was not immediately possible to confirm that figure.

The Britain-based Syrian Observatory for Human Rights said Turkish warplanes struck villages near the camp on Sunday. It said camp residents fled as clashes broke out between Turkey-backed Syrian fighters and Kurdish forces, without providing an exact number.

The Kurdish-led Syrian Democratic Forces were a key US ally in the war against the Daesh group and drove the extremists from most of the territory they once held in northeastern Syria. The force swept up thousands of Daesh fighters and their family members in the campaign, and has warned it may not be able to maintain its various detention centres as it struggles to repel the Turkish advance.