Both sides in Ukraine's conflict have traded bitter recriminations over Friday's deaths from the Odessa rioting.
The violence began with street fighting between supporters of Ukrainian unity and activists who support Russia, with at least three people were reported killed by gunfire. The government opponents took refuge in a large trade union building, which then caught fire as opposing sides hurled Molotov cocktails at each another.
Odessa Police Chief Petr Lutsyuk issued a statement Saturday calling for calm in the city of about 1 million, but hours later he was fired by the interior minister.
The U.S. ambassador to Ukraine, Geoffrey Pyatt, said he was disturbed by signs that some of the police in Odessa may have been complicit in allowing the violence to get out of control.
"That's something which Prime Minister Yatsenyuk spoke to today," Pyatt said on CNN's "State of the Union." ''And I see that he's already brought some major changes in the security leadership there in Odessa, which I think reflects the deep concern about the role that the security establishment played in Friday's violence."
Late Sunday, about 300 supporters of the Kiev government gathered outside the regional police headquarters to demand that the armed pro-Russian demonstrators be punished. Carrying sticks and bats, they chanted, "Glory to Ukraine!"
"The Russians bought off our police," said Andrei Shpak, who wore a balaclava to hide his face and carried a Ukrainian flag. "We're angry that the separatists were set free and we demand that anyone who calls for the breakup of Ukraine be punished."
Their demands were addressed to the police chief who replaced Lutsyuk.
The victims of Friday's fire have become a rallying point by pro-Russian groups in eastern Ukraine. In a position eagerly promoted by the Kremlin, critics of the authorities in Kiev have blamed the deaths on radical ultranationalists, abetted by the government.