Kurdish rebels have attacked Turkish military units in south-eastern Turkey, sparking clashes in which 10 rebels and eight soldiers died, authorities said.
The attack happened in Daglica area of Hakkari province, which borders northern Iraq's Kurdish areas.
Sixteen Turkish soldiers were injured in the attack, the governor's office in Hakkari said in a statement.
A similar rebel attack in the same area in late 2007, in which 12 Turkish soldiers died, triggered an eight-day incursion by the Turkish military into Iraq in February 2008. Rebels use northern Iraq as a base from where to launch attacks on Turkish troops.
The rebel group, the Kurdistan Workers' Party, or PKK, is fighting for autonomy in south-east Turkey. Tens of thousands have died since it took up arms in 1984.
Tuesday's attack came amid efforts by the government to try to reconcile with the Kurdish minority through granting more cultural rights.
Prime Minister Recep Tayyip Erdogan recently announced plans to introduce elective Kurdish lessons in schools, after allowing Kurdish language broadcasts on television.
Turkey refuses demands by Kurdish activists, rebels and politicians for full education in Kurdish, fearing it could divide the country along ethnic lines. An estimated 20% of Turkey's 75 million are Kurds.