Turkey's armed forces have killed 23 Kurdish fighters in clashes in eastern Turkey and with air strikes, according to the general staff.

Security sources said on Saturday that warplanes and attack helicopters fired on a mountainous, forested area in the eastern province of Tunceli after military drones spotted a group of about 20 PKK fighters there on Friday.

The armed forces' statement said three of the fighters were killed in the air strikes.

INFOGRAPHICS: Major Kurdish factions

Elsewhere, in the southeast of the country, the army killed eight PKK fighters in Silvan, six in Nusaybin and three each in the towns of Sirnak and Yuksekova on Friday, the statement said.

Thousands of fighters and hundreds of civilians and soldiers have been killed since the PKK resumed its fight for Kurdish autonomy last summer, ending a two-year ceasefire and shattering peace efforts.

Turkish fatalities

Turkish warplanes have frequently struck PKK targets since the conflict revived, mainly hitting the group's bases in northern Iraq.

Security sources said on Friday that four Turkish soldiers were killed and two wounded when a bomb hit a military vehicle travelling in the southeastern province of Mardin.

OPINION: No to terrorism, no to double standards

The government has ruled out any return to the negotiating table and has said it will crush the PKK, which is considered a terrorist organisation by Turkey and its Western allies.

The PKK’s abandoning of a ceasefire prompted a conflict that has claimed more than 40,000 lives since 1984.

The violence wrecked a peace process that was seen as the best chance at ending one of Europe's longest-running conflicts.

Turkish President Recep Tayyip Erdogan has repeatedly vowed to stamp out the conflict in southeastern Turkey once and for all.

Various towns in the region have been under on and off curfews due to army operations against the PKK.

Inside Story - Is the West too soft on the PKK?

Source: Agencies