After failed overnight talks with the opposition, president Viktor Yanukovych urged its leaders to "distance themselves from radical forces", saying it was "not too late to stop the conflict".
Riot police are continuing to storm the main anti-government protest camp. Activists blamed the authorities for the worst violence in months of unrest.
Explosions are taking place, fireworks are being thrown and large fires can been seen on Independence Square – known as the Maidan.
The latest assault began shortly after 4 a.m. local time, when the police tried to move on the protesters’ tents. Several were set ablaze, and water cannon was later used.
