Kurdistan Workers Party (PKK) militants attacked a military outpost and a police car in southeast Turkey overnight, killing one policeman, officials and security sources said on Sunday, part of a surge in violence between the PKK and the state.
The Turkish military launched an air campaign against PKK camps in northern Iraq on July 24.
State-run Anadolu news agency said more than 260 militants had been killed, including senior PKK figures, and more than 400 wounded until August 1.
Anadolu did not give a source for the figures. The latest fighting threatens a fragile peace process between the two sides.
The PKK had already said earlier in July that it was stepping up attacks and accused Turkey of violating a 2013 cease-fire.
Late on Saturday, PKK gunmen opened fire on a police car in the town of Midyat in Mardin province, killing one officer and wounding another, the Mardin governor's office said in a statement.
PKK fighters also fired rockets at a military outpost in the Bulanik district of Mus province, triggering a brief gunfight, security sources said. There were no reports of casualties.
A day earlier six people were killed in clashes between security forces and militants in the mainly Kurdish southeast.
Alarmed at the rising violence, Turkey's pro-Kurdish party leader urged the militant Kurdistan Workers Party (PKK) on Saturday to "remove its finger from the trigger" and said the government should launch talks to halt the violence.
Anadolu said 24 security force members had been killed in militant attacks in the last month, and 12 PKK fighters had been killed in clashes.
As well as PKK targets, Turkish jets have hit Islamic State positions in Syria. Ankara has also allowed the U.S.-led coalition targeting the IS militants to use its air bases.
The PKK, designated a terrorist group by Ankara, the United States and European Union, launched its insurgency in 1984. In 2012 Ankara launched a peace process with PKK leader Abdullah Ocalan, jailed on Imrali island south of Istanbul.
More than 40,000 people have been killed in the conflict.