"We aren't managing to prevent terrorist infiltrations despite all precautions taken and the deployment of cannons and tanks" along the Turkish-Syrian border, Gul told Turkish press from New York, where he is attending the UN General Assembly.

"Radical groups are a big worry when it comes to our security," the Hurriyet daily quoted him as saying.

Turkey, which shares a 900-kilometre (560-mile) border with Syria, is currently sheltering more than 500,000 Syrians who have fled the fighting in their country.

Last week, Turkey temporarily shut part of its border after fighting raged between foreign-backed Syrian militants and an Al Qaeda front group in the northern town of Azaz.

Security at Turkish border town with Syria exacerbates ever since fighting among rival anti-Syrian groups spread throughout the region.

On Wednesday, at least five members of the Northern Storm Brigade, an anti-Syrian militant group controlling a border town were killed in conflicts with the al Qaeda linked Islamic State of Iraq and the Levant (ISIL).

The fighting which continued on Thursday indicates deep gulf between militant groups.

MRKD/NJF