Around 2,000 demonstrators huddled around fires in sub-zero temperatures at their main tent protest camp in Kyiv's Independence Square on Tuesday, according to the Reuters news agency.

Many of them had regrouped there after riot police moved in late on Monday to disperse protesters and remove barricades that the demonstrators had set up to blockade government buildings, including the cabinet offices, parliament, and the presidency for several days.

Some clashes were reported as police moved in, and opposition leader Oleh Tyanhybok told Ukrainian media outlets that several protesters were injured overnight.

Opposition lawmaker Yuriy Syrotyuk of the nationalist Freedom Party said at least 10 people had been injured.

However, news agencies said it appeared that the confrontations overnight were on a much smaller scale than a violent crackdown over a week ago, which sparked outrage and led to even bigger demonstrations.

Officials with jailed former Prime Minister Yulia Tymoshenko's Fatherland Party also reported that security forces had broken into their headquarters and confiscated computer equipment.

Efforts to break the stalemate

The flag was reported to be flying over the offices of President Viktor Yanukovych on Tuesday morning, indicating that the embattled head of state was at work.

The president was planning to hold talks with three of his predecessors on Tuesday to explore ways of resolving the political standoff, which began almost two weeks ago, when he balked at signing an association agreement with the European Union. The pro-EU and anti-government protesters fear this could be the start of a shift away from Europe and towards even closer ties with Russia.

Catherine Ashton, the EU's foreign policy coordinator, was also expected in the Ukrainian capital on Tuesday, where she hoped to use emergency talks with President Yanukovych to help defuse the crisis.

On Tuesday, Ashton expressed concern about the situation in general and the reported raid on the Fatherland Party's headquarters in particular.

Ashton called on the Ukrainian authorities "to exercise utmost restraint and refrain from any further use of force, in order to give space for a negotiated solution out of the current political stalemate."

pfd/kms (AFP, Reuters, AP, dpa)