The head of the pro-Kurdish opposition HDP party has accused the ruling AKP of orchestrating nationalist attacks and pushing Turkey towards civil war.
No-one has been killed, but Selahattin Demirtas said his supporters were facing a "campaign of lynching".
Later Mr Demirtas was prevented from going to the south-eastern city of Cizre, currently under military curfew.
Violence between the army and the militant Kurdish PKK has escalated since a ceasefire collapsed in July.
Turkey is to hold elections in November after inconclusive polls in June.
PM's denunciation
As the atmosphere in Turkey becomes increasingly febrile, Mr Demirtas questioned whether the vote could even go ahead while temporary military zones were in place in 100 areas of Turkey's mainly Kurdish south-east. He said there had been 400 attacks on HDP offices in two days.