Turkish security forces killed 11 Kurdish militants in clashes near the borders with Syria and Iraq, while one soldier was killed in a firefight elsewhere in southeast Turkey, state authorities said on Friday.
Violence has wracked the mainly Kurdish region since a two-year Kurdistan Workers Party (PKK) ceasefire broke down in July, leaving hundreds dead and tearing apart a peace process launched by Ankara with the group's jailed leader in late 2012.
President Tayyip Erdogan has vowed to fight the PKK until all of its militants are "liquidated".
The PKK fighters were killed in an operation by Turkish forces in the Cizre and Silopi districts of Sirnak province on Thursday, the provincial governor's office said in a statement.
Further north in Van province, security forces launched a dawn operation on Friday after a tip-off that PKK members were holed up in a house in the Ercis district, the armed forces said on their website. It said one soldier was killed and three wounded in the resulting clash, which was ongoing.
The PKK took up arms against the state in 1984, and more than 40,000 people, mostly Kurdish militants, have died in the conflict. It is listed as a terrorist organisation by Ankara, the United States and European Union.