The fighting erupted overnight during a military operation near the village of Suveren, in Bingol province, against the separatist Kurdistan Workers' Party (PKK), the sources said.

Listed as a terrorist group by Turkey and much of the international community, the PKK has been fighting for self-rule in the mainly Kurdish southeast since 1984. The conflict has claimed more than 37,000 lives.

Turkey has stepped up action against the group since December and has carried out several air strikes and a week-long ground incursion into northern Iraq, where it says more than 2,000 PKK rebels take refuge.

In the latest strike, Turkish jets and artillery targeted a group of PKK rebels across the border on Friday and Saturday.