The militants were shot dead in the countryside in Tunceli province, where an army operation against the outlawed Kurdistan Workers' Party (PKK) was continuing, the local governor said in a statement carried by Anatolia news agency.

Separately, officials said that a bomb, believed to have been activated by remote control, went off late Saturday on a railroad in the southeastern province of Mus, derailing a passing freight train and damaging eight of its wagons.

The authorities believe the blast was the work of the PKK, blamed for similar attacks in the past, the sources said.

Last month, a bomb damaged a freight train in the same province, and in July last year five railway security guards were killed when a bomb ripped through a train in neighboring Bingol.

The PKK, blacklisted as a terrorist group by Turkey, the European Union and the United States, has stepped up its violent campaign this year.

The Kurdish conflict in Turkey has claimed more than 37,000 lives since 1984 when the PKK took up arms for self-rule in the mainly Kurdish southeast.