Pro-Russian demonstrators in eastern Ukraine smashed their way into public buildings and burned Ukrainian-language books on Sunday in further protests following two deadly clashes in the region last week.
Violence in eastern Ukraine has prompted warnings from Moscow that it is prepared to "defend" the rights of residents who disagree with the new pro-Western authorities in Kiev.
In Kharkiv, Reuters Television footage showed pro-Russian activists breaking into the headquarters of a Ukrainian cultural center, removing Ukrainian-language books and setting them alight in small bonfires in the street.
Protesters moved through the city centre trailing banners dozens of metres (yards) in length bearing the Russian tricolour.
On Friday, two pro-Russian protesters were killed by buckshot after a confrontation outside the same cultural centre with activists from Ukraine's extreme-right Right Sector group.
In Donetsk, the heart of the Donbass coalfield, where a pro-Ukrainian activist died in clashes on Thursday, 5,000 protesters roamed from a central square to several public buildings, smashing doors and windows as they went.
The massed for a time outside the local prosecutor's office before lines of riot police let them through and they pushed their way inside with poles and sticks. A small group clambered onto the roof, snatched away the blue and yellow Ukrainian flag and waved red-white-and-blue Russian standards.