70,000 Syrian Kurds flee from Islamic State in 24 hours

As many as 70,000 Syrian Kurds have poured into Turkey since Friday fleeing an offensive by Islamic State jihadists in northeastern Syria, the UN's refugee agency has said.

Syrian Kurds carry their belongings near the Syrian border at the southeastern town of Suruc in Sanliurfa province, on September 20, 2014.

The UNHCR "is stepping up its response to help Turkey come to the aid of an estimated 70,000 Syrians who crossed into Turkey in the last 24 hours," the agency said in a statement.

The exodus was prompted by intense clashes between IS and Kurdish fighters trying to hold off an assault on the town of Ain al-Arab, known as Kobane by the Kurds.

Since Tuesday night, IS fighters have been advancing on the town, hoping to seize it and secure their control over a large swathe of Syria's northern border with Turkey.

The group has quickly seized at least 63 surrounding villages, although the Syrian Observatory for Human Rights, a Britain-based monitor, said 18 IS fighters were killed in clashes overnight.