Dozens of nationalist protesters marched on the the headquarters of the pro-Kurdish Peoples' Democratic Party (HDP) in Ankara, throwing stones and ripping down the sign outside, pictures broadcast by the CNN-Turk channel showed.

"Our headquarters in under attack but the police is not performing its duties," the party said on its official Twitter feed.

Smoke was seen coming from the building, an AFP photographer said, although police eventually dispersed the demonstrators.

Pictures posted on social media suggested the interior of the building had been badly damaged in the attack.

Nationalists accuse the HDP of being the political wing of the Kurdish militant Kurdistan Workers Party (PKK), which has carried out a series of deadly attacks against security forces in recent days. The HDP denies this is the case.

In the southern resort city of Alanya, the local HDP headquarters was set on fire, sending yellow flames into the night sky, CNN-Turk reported.

Similar nationalist demonstrations were taking place across Turkey, with protesters damaging HDP buildings in at least six other cities, it said.

The attacks come amid rising tensions in Turkey and warnings the country is on the verge of a protracted civil conflict with its Kurdish minority.