Two young men were shot to death and one tumbled from a high ledge while fighting the police.
The lethal turn seemed likely to escalate tensions in the already roiling capital.
By afternoon, riot police and protesters were in a running skirmish along a central street leading to the Parliament building, fighting amid the burned-out shells of police vans.
On the government side, Prime Minister Mykola Azarov, in a statement to the cabinet, called the protesters “terrorists” and said the movement’s leaders should bear responsibility for the deaths.
A leading opposition party, Fatherland, said it had declared a parallel government called a “People’s Council.”
The opposition has asked supporters to come out en masse at a rally after working hours Wednesday.
Two young men died from gunshot wounds on the street near the Parliament Ukraine, known as the Verkhovna Rada, which is the epicenter of the violence, according to medics who treated them near the site, according the prosecutor’s office.
It was not immediately clear whether they were struck by rubber bullets or live ammunition.
The Interfax news agency cited a medic at the scene as saying it appeared a sniper had shot one of the men.
Another protester died nearby after falling from a colonnaded entrance to a soccer stadium.
The fighting between the riot police units called by their Ukrainian name the Berkut and protesters began around dawn on a cold morning, after a mostly calm night.
The Ukrainian crisis escalated sharply last week after President Viktor F. Yanukovich signed new laws restricting public assembly and limiting media freedoms.
That revived a movement that had been fading, as its political leaders were focusing their efforts instead on elections scheduled for next year.
Opposition leaders say Mr. Yanukovich’s government has also rebuffed all offers of negotiations, making an already volatile situation worse.
“Few days are left, or maybe even hours, when solving the political process is possible through negotiations,” Arseniy Yatsenyuk, a leader of the opposition Fatherland Party, said Tuesday.
“This should be done while people are still willing to listen to politicians and accept the path to political resolution of the crisis.”
The Fatherland Party, which is led by the imprisoned former prime minister, Yulia V. Tymoshenko, issued a statement saying it and other opposition factions would form a parallel government to be called the “People’s Council” whose composition would be clarified at the rally planned for Wednesday evening.
It would include elected members of Parliament and regional governments, the statement said.
It was unclear how much power this body would claim for itself.
“People’s government is what we have declared,” the statement said.
Opponents of the current government said three recent actions had been intended to incite the more radical protesters and sow doubt in the minds of moderates: the passing of laws last week circumscribing the right of public assembly; the blocking of a protest march past the Parliament building on Sunday; and the sending of cellphone messages on Tuesday to people standing in the vicinity of the fighting that said, “Dear subscriber, you are registered as a participant in a mass disturbance.”
The American Embassy in Kiev said on Wednesday it had revoked the visas of several people suspected of abetting violence between police and protesters last year but did not identify these people, citing the confidentiality of visa applications.
The statement said the State Department was now considering further action against “those responsible for the current violence.”
The European Union called on the government and opposition to begin “genuine dialogue” and the bloc’s foreign policy chief, Catherine Ashton, said in a statement “I strongly condemn the violent escalation of events in Kiev overnight leading to casualties.”
Russia’s foreign minister, Sergey V. Lavrov, blamed politicians from the European Union and the United States for encouraging the fighting over the past three days.
The situation in the city, he warned, was “getting out of control.”
“It seems someone is interested in this chaos,” Mr. Lavrov said Tuesday at a news conference in Moscow.
Source: The New York Times