Media reports in Turkey say government warplanes have bombed Kurdish nationalist rebels in southeast of the country in the first significant air operation against the group since peace talks began two years ago.
The Hurriyet newspaper says the jets hit Kurdistan Workers' Party (PKK) targets in Hakkari province on Sunday.
The bombings are said to be a response to shootings by the PKK at a military outpost in the area. They come amid increased internal tension over Turkey's inaction against the Islamic State.
Protesters in recent weeks have called for the Turkish military to intervene across the Syrian border, where IS militants have surrounded Kobani.
The PKK issued a call to arms in September for Kurds to defend the largely Kurdish town.
The renewed conflict between Turkey and the PKK jeopardizes a fragile peace process launched by Ankara and rebel leadership in 2012 after three decades of insurgency killed more than 40,000 people.