Fighting erupted Thursday in a mountainous area in Bingol province after the army launched an operation against the separatist Kurdistan Workers Party (PKK) to thwart "winter positioning" preparations, said the sources, who spoke on condition of anonymity.

They said six soldiers were wounded, three by gunfire and the others in the explosion of a landmine planted by the rebels.

Security forces destroyed several militant hideouts and the operation is continuing, the sources said.

The Bingol governor's office reported fighting in the region Thursday evening, but said there were no casualties.

The PKK, listed as a terrorist group by Ankara and much of the international community, called a unilateral ceasefire on October 1 in what it described as an effort for a peaceful resolution of the Kurdish conflict.

But the truce, like previous ones called by the group, was rejected by Turkey, although fighting has markedly decreased since then.

More than 37,000 people have been killed since the PKK took up arms in 1984 for self-rule in Turkey's mainly Kurdish southeast.