As anti-government protesters clash with Ukrainian riot police in Kiev, EU leaders are planning to discuss sanctions against the Yanukovych administration at an emergency meeting.
So far this week, at least 26 people have been killed, including 10 police officers, and 241 have been injured in the worst violence to hit Ukraine since it gained independence from Russia.
Ukrainian President Viktor Yanukovych accused pro-European opposition leaders of trying to seize power, while European Union leaders condemned “the unjustified use of excessive force by the Ukrainian authorities”, and said they were preparing targeted sanctions against the government.
The White House said riot police should be withdrawn from Kiev’s Independence Square, where the violence has flared.
But the Ukrainian security services said they said they were launching “anti-terrorist operations” across the country following th seizure of government buildings, arms and ammunition dumps by “extremist groups”.
Various objects were set on fire by protesters in and around Independence Square. They threw various objects, including Molotov cocktails, at large vehicles, which appeared to have been trying to break up barricades on the square.
Demonstrators have been occupying central Kiev for almost three months in protest at President Yanukovych’s decision to reject a trade deal with the EU in favour of economic links with Russia.
Russian President Vladimir Putin‘s spokesman insisted the Kremlin was sticking to a policy of not intervening in Ukraine, although his point man has called for action to crush the protests.
The Kremlin said Mr Putin and Mr Yanukovych spoke by telephone, calling the events an attempted coup.
Moscow announced the resumption of stalled aid to Kiev on Monday with a $2m cash injection hours before the crackdown began.
After a night of petrol bombs and gunfire on Independence Square, President Yanukovych said he had refrained from using force since unrest began but was being pressed by “advisers” to take a harder line.
“Without any mandate from the people, illegally and in breach of the constitution of Ukraine, these politicians – if I may use that term – have resorted to pogroms, arson and murder to try to seize power,” the president said.
He declared Thursday a day of mourning for the dead. A senior opposition leader, world champion boxer-turned-politician Vitaly Klitschko, walked out of a meeting with President Yanukovych during the night, saying he could not negotiate while blood was being spilt.
When fighting subsided at dawn, the square resembled a battle-zone, the ground charred by Molotov cocktails. Helmeted young activists used pickaxes, and elderly women used their bare hands, to prise up paving to stock as ammunition.
Police and opposition said many were killed by gunshot, but the interior ministry said that five of the dead policemen had died of identical wounds from sniper fire to the head and neck. Journalists saw some hardline protesters manning barricades armed with rifles, including one with a telescopic sight.
European Commission President Jose Manuel Barroso said the 28-nation bloc was set to impose sanctions against those blamed for the bloodshed.
“We have… made it clear that the EU will respond to any deterioration on the ground,” Mr Barroso said in a statement. “We therefore expect that targeted measures against those responsible for violence and use of excessive force can be agreed by our member states as a matter of urgency.”
These measures include include travel bans and asset freezes.
Prime Minister David Cameron called on the Ukrainian authorities to pull back their forces.
“I am deeply concerned by the scenes we are witnessing in Ukraine,” he said. “The violence on all sides is completely unacceptable and President Yanukovych has a particular responsibility to pull back government forces and de-escalate the situation.
“President Yanukovych should be under no doubt that the world is watching his actions and that those responsible for violence will be held accountable.”