Three Turkish policemen were killed after Kurdish insurgents opened fire on a police car in the southeast near the border with Iraq, security sources said, the latest in a string of clashes in the mainly Kurdish region.
The southeast has been rocked by a spate of clashes with insurgents that has left hundreds dead since a two-year-old ceasefire between the Turkish state and Kurdistan Workers Party (PKK) militants broke down in July.
Security sources said a wide scale operation against the PKK militants started after the attack late on Tuesday, and one police officer was being treated for his wounds.
Also on Tuesday, one Turkish soldier was killed and 20 others were injured in two separate attacks in the region.
Areas of the southeast have been intermittently subject to round-the-clock curfews in response to the conflict. Security sources said six people had died in clashes in the town of Silvan in Diyarbakir province since a curfew was imposed there eight days ago.
Last Thursday, the PKK ended a month-old ceasefire it had declared before the November 1 election. That vote was won by the AK Party of President Tayyip Erdogan, who subsequently vowed to fight the PKK until all fighters were "liquidated".
Erdogan has overseen a peace process launched with jailed PKK leader Abdullah Ocalan in late 2012 but talks were frozen in April.
The PKK, which wants autonomy for Turkey's large Kurdish minority, is listed as a terrorist organization by Ankara, the United States and European Union. It took up arms against the Turkish state in 1984 and more than 40,000 people, mostly Kurdish militants, have died in the conflict.
