Ukrainian riot police moved in force early on Wednesday into part of the Kiev square where protesters are demonstrating against a government decision to rebuild trade ties with Russia rather than move closer to the European Union.
Reuters witnesses said there was no immediate sign of violence as police, with shields and helmets, entered Independence Square in the heart of the snowbound capital where the demonstrators have been camping out for the past 10 days.
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Protesters were herded back around a stage in the center of the square, from which a singer urged police through a loud hailer: "Do not harm us!"
Some held their mobile phones in the air like candles and sang the national anthem, while church bells rang out from a cathedral about 2 km (1 mile) away as in times of danger centuries ago.
But police stopped operations, while remaining in place, and made no move to pull down tents in the square where protesters have been living. Several hundred demonstrators remained camped there after the initial police action.
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Police moved in from the northern end of the square after pulling down barricades which had been thrown up across the road by protesters. They also dismantled barricades and tents in front of City Hall, about 300 meters (yards) away, where protesters who have been occupying the premises had barricaded themselves in.
President Viktor Yanukovich, whose government walked away from signing a major trade pact with the European Union on November 21, said on Tuesday he was committed to European integration but that Ukraine had no choice but to restore trade relations with Russia.