DHAKA: Some 66,000 refugees - mainly Syrian Kurds - have crossed into Turkey in 24 hours as Islamic State militants advance in northern Syria, BBC reports.

Turkey opened its border on Friday to Syrians fleeing the Kurdish town of Kobane in fear of an IS attack.

The UN refugee agency said it was boosting relief efforts as hundreds of thousands more could cross the border.

IS controls large areas of Syria and Iraq and has seized dozens of villages around Kobane, also called Ayn al-Arab.

Turkey - which shares a border with Iraq and Syria - has taken in more than 847,000 refugees since the uprising against Syrian President Bashar al-Assad began three years ago.

But the opening of the border has seen a dramatic increase in the past 24 hours.

Separately, a Turkish government official told the BBC's Mark Lowen that the number is as high as 66,000.

BDST: 1127 HRS, SEP 21, 2014