Top Western diplomats headed to Kiev today to try to defuse a stand-off between Ukrainian President Viktor Yanukovych's government and thousands of demonstrators, following a night in which police in riot gear dismantled protesters' encampments outside government buildings.
Demonstrators have occupied the Ukrainian capital for weeks protesting at Mr Yanukovych's decision to freeze ties with the European Union and lean towards Russia instead.
Riot police in full gear flooded Kiev, confronting protesters throughout the night on snowy streets, while a leading opposition party said heavily armed security forces broke into its offices and seized computer servers.
Mr Yanukovych is planning talks today with Ukraine's three former presidents in a search for a resolution to the crisis.
An opposition leader, Oleh Tyanhybok, was quoted by Ukrainian media as saying several protesters were injured in one of the confrontations, in which police tore down small tent camps locking access to government buildings.
There were no immediate official figures on injuries, but the incident appeared to be less violent than the club-swinging police dispersals of demonstrators a week and a half ago which galvanised anger.
Police moves yesterday and today were against encampments set up after Sunday's rally and no action was taken against the extensive main camp in Kiev's central Independence Square, where crowds gather around the clock.
The protests, in their third week, started after Mr Yanukovych backed away from signing an agreement on deepening ties with the European Union, a pact which many Ukrainians desired in order to tilt West and reduce Russia's influence on the former Soviet republic.
Police violence against those demonstrations outraged many and drove hundreds of thousands of people into the streets the past two Sundays, turnouts perhaps larger even than the mass protests of the 2004 Orange Revolution that forced a re-run of a fraudulent presidential election. On Sunday protesters also toppled a landmark statue of Soviet leader Vladimir Lenin in a symbolic defiance of Russian influence.
EU foreign policy chief Catherine Ashton and US Assistant Secretary of State Victoria Nuland were expected in Kiev today, to meet Mr Yanukovych and the opposition.
Mr Yanukovych was also due to meet his three predecessors, including Viktor Yushchenko, who defeated him in the election forced by the 2004 protests, and Leonid Kuchma, who as president opted against the use of force against Orange Revolution demonstrators.
The night-time confrontations were tense and angry, but the rally on Independence Square retained an incongruous air of merriment. Hyper-energetic pop star Ruslana led an aerobic dance routine to warm the demonstrators against the minus 5C freeze and servers with trays of hot tea passed through the crowd.
Last night, Ostap Semerak, of the Fatherland Party, told the Associated Press that troops broke into the party's offices, some climbing in through its windows.
The troops left after confiscating some computer equipment, he said. An Associated Press reporter later saw broken glass and smashed computers in the offices. Party member Marina Soroka also said the troops surrounded and blockaded several opposition-minded Ukrainian media outlets, making their and other media websites inaccessible.
The Fatherland Party is headed by imprisoned former Prime Minister Yulia Tymoshenko, a longstanding foe of Mr Yanukovych, and is the largest opposition grouping in the parliament. Critics say Ms Tymoshenko's conviction on abuse of office charges was a case of political revenge.
Ukraine's political stand-off has been aggravated by its rapidly deteriorating finances. The economy has been in recession for more than a year, and the government is in desperate need of foreign funding to avoid a default. As talks stalled with the International Monetary Fund, Mr Yanukovych has sought a bailout loan from Russia.