US Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov meanwhile tried on August 26 at a meeting in Geneva to finalize an agreement on fighting Islamist militants in Syria. Such a deal could in theory pave the way for a political transition to end the five-year conflict.
Turkey, a NATO member and part of the US-led coalition against Islamic State, has seen a series of deadly bombings this year blamed on the radical Islamists. But it also fears Kurdish militias in Syria will seize a swathe of border territory and embolden Kurdish insurgents on its own soil.
President Tayyip Erdogan said the bombing in Sirnak province would increase Turkey's determination as it fights terrorist groups at home and abroad. Yildirim said there was no doubt the Kurdistan Workers Party (PKK), which has waged a three-decade insurgency for Kurdish autonomy, was responsible.
After he spoke, the PKK claimed responsibility for the attack on the police headquarters, according to a website affiliated to the group.
Syria has condemned the Turkish operation, codenamed "Euphrates Shield", as a breach of its sovereignty. Turkish special forces, tanks and jets launched the incursion in support of Syrian rebels, mostly Turkmen and Arab, who quickly took the border town of Jarablus from Islamic State on August 24 .
An alliance of 23 Kurdish parties in Syria also condemned the Turkish operation on August 26 In a joint statement, they called for a complete withdrawal of all Turkish forces from the country and accused Ankara of trying to occupy Syria under the pretence of fighting terrorism.
Turkish military vehicles shuttled in and out of Syria on August 26.
