Ukrainian troops battle pro-Russian separatists in Slovyansk

Avakov also said on Monday he sent a new special forces unit into the southern port city of Odessa after the “outrageous” failure of police to tackle pro-Russian separatists in a weekend of violence that killed dozens.

Odessa, a southwestern port with a broad ethnic mix, including Russians, Ukrainians, Georgians and Tatars, is seen in Kyiv as something of a bellwether, a warning of danger if rebellion spreads beyond the Russian-speaking east.

Avakov said the new Odessa force was based on “civil activists” who wanted to help the Black Sea city “in these difficult days.” The entire leadership of the local police had been sacked and could face criminal action.

The Odessa violence was the deadliest since Moscow-oriented President Viktor Yanukovych fled to Russia in February and pro-Russian militants launched uprisings in the industrial east.

“The police in Odessa acted outrageously, possibly in a criminal fashion,” Avakov said on his Facebook page. “The ‘honor of the uniform’ will offer no cover.”

Ukrainian leaders have made it clear they see the police force across wide areas of the country as unreliable in the face of rebellion, which they say is backed by Moscow and led on the ground by Russian special forces. The units Avakov referred to emerged partly from the uprising against Yanukovych.

Odessa, a city of a million people, has two ports, including an oil terminal, and is a key transport hub.

Kyiv’s anger on Monday focused on the Odessa police decision to release 67 largely pro-Russian militants after supporters besieged and stormed a police station on Sunday.

For weeks, Odessa had remained largely peaceful even as violence erupted across eastern Ukraine. But 46 people died Friday after riots broke out there between pro-Russia and pro-Ukraine groups and a government building was set on fire.

While Russian President Vladimir Putin has made no public comment on the situation in Ukraine since the Odessa fire, which killed more than 30 Russia supporters, several Russian politicians have ramped up their anti-Ukraine rhetoric, and Russian state media outlets have referred to the fire as genocide.