At least 19 people have died in southeast Turkey after Kurdish rebels launched an attack on a Turkish border post, according to local media.
Rebels fired rocket launchers on an army post in Hakkari province just after midnight, NTV in Turkey said.
Turkish military jets are pursuing them and bombing their escape routes, NTV said.
Several thousand Kurdistan Workers Party (PKK) rebels are believed to be based in hideouts in northern Iraq.
According to the governor for Hakkari province, Orhan Alimoglu, six soldiers, two village guards and 11 Kurdish rebels were killed in the attack near the village of Gecimili.
He said 15 soldiers were injured in the incident.
The number of clashes between the PKK and the Turkish armed forces has risen in southeast Turkey over the past year.
A series of clashes in June left dozens dead.
The PKK is classified as a terrorist organisation by the EU and the US.
It launched a guerrilla campaign in 1984 for an ethnic homeland in the Kurdish heartland in the south-east of Turkey.
It has now dropped its claim to an independent Kurdish state, but says it is fighting for autonomy and the cultural rights of the Kurdish people.
