At least seven Turkish soldiers have been killed and 63 wounded in a rocket attack on their military convoy in the southeast of the country, local security sources have said.
The sources, speaking on condition of anonymity, said the convoy was hit by rockets fired by suspected Kurdistan Workers' Party (PKK) fighters on Tuesday on a highway on the outskirts of Bingol province.
The attack triggered a fire that wounded dozens of soldiers who were travelling on an army bus.
Hurriyet newspaper reported on its English edition website that the unarmed soldiers were returning from leave.
Eight of the injured soldiers were in "critical condition", the paper quoted Bingol governor Mustafa Hakan Güvençer as saying. He added that four of them were sent to a hospital in Elaz with ambulance aircraft.
The Turkish army retaliated with an immediate operation backed by air power in the larger Bingol area to capture the members of the PKK who staged the attack, Anatolia news agency reported.
Rare rocket attack
The assailants were identified by witnesses as three men who drove away in a car after the attack, who were believed to be travelling with heavy explosives on board, Turkey's NTV private news channel reported.
PKK attacks against Turkish security forces have increased in the Kurdish-majority southeast, but a powerful rocket ambush carried out in daylight marks a rare incident.
It comes a day after Recep Tayyip Erdogan, Turkey's prime minister, said 500 Kurdish fighters had been killed over the past month.
Last Sunday, eight police officers were killed in a roadside mine blast in a district of the same Bingol province.
This summer has seen a showdown between Turkish forces and the PKK, who have ramped up their attacks in recent months, triggering full-fledged military operations in the region.
The PKK, considered a terrorist group by Turkey and much of the international community, took up arms for an autonomous area in the southeast in 1984 in a conflict that has claimed about 45,000 lives.