Ukraine erupted into violence again after an overnight truce that never really took hold was bloodily smashed.

Dozens were killed. The toll was impossible to verify and constantly rising, though some estimates put the number at around 100 dead in the last week as police and far-right protesters engaged in an almost-medieval melee.

Protesters also seized 67 police officers and paraded them through the protest camp, the interior ministry said.

An opposition MP said they were being held in Kiev's occupied city hall.

Western powers continued to stick their oars in, with the White House saying it was "outraged by the images of Ukrainian security forces firing automatic weapons on their own people."

The US said on Wednesday that it had imposed travel bans on around 20 senior members of the Ukrainian government.

And EU states began mulling a targeted sanctions programme against Ukraine after a planned meeting with President Viktor Yanukovych was scrapped.

Mr Yanukovych had said the truce was the start to negotiations with the aim of ending bloodshed and "stabilising the situation in the state in the interests of social peace."

But the vocal and violent fascist elements within the protests never held to the ceasefire.

One camp commander, Oleh Mykhnyuk, told the Associated Press that even after the alleged truce protesters still threw petrol bombs at riot police on the square.

As the sun rose, police pulled back, the protesters followed them and police then began shooting at them, he said

Western powers, whose attempts to woo Ukraine away from Russian influence sparked the protests three months ago, blamed the government for sparking the confrontation.

But the Communist Party of Ukraine pointed out that the extremist groups behind the worst of the violence were "sponsored not only by Ukrainian oligarchs but also major Western capital, which is interested in destabilising the situation in Ukraine."

It said the nationalist forces were trying to mount a coup by "the most treacherous methods of warfare," including terrorism and using women and children as human shields.

The party said leaders and activists of the fascist forces must be prosecuted.