The casualties included three soldiers and three village guards -- government-armed Kurdish militia supporting the army against the militants.

They were participating in a security operation near the town of Semdinli against the outlawed Kurdistan Workers' Party (PKK).

Two other soldiers were wounded in the fighting, the governor's statement said.

The PKK -- considered a terrorist group by Turkey, the United States and the European Union -- has been fighting for a separate state in the mainly Kurdish southeast and east of Turkey since 1984.

The conflict has left more than 37,000 dead.

Turkey alleges that thousands of PKK militants are holed up in rear bases in northern Iraq and has carried out several cross-border air strikes and a week-long ground incursion against rebels bases since December.