Unrest in Ukraine spread to the south as thousands of pro-Russian protesters attacked Odessa's police headquarters after a fire killed dozens of their comrades, in violence Kiev charged was a Russian plot to "destroy" the country.
Increasing tension in the southern port city threatened a new front in the Ukrainian government's battle against pro-Moscow militants, with an expanded military operation under way in the east against gunmen holding more than a dozen towns.
A blaze at a trade union building in Odessa Friday left 42 people dead - most of them pro-Russian militants - after running battles with pro-Kiev protesters.
Yesterday police released 67 separatist militants they had detained following the violence in a bid to calm thousands of pro-Moscow supporters who had gathered outside Odessa's police headquarters. One person, though, was reported wounded by gunfire in the city.
Three loud explosions were also heard by AFP journalists after 8:00 pm yesterday (2230 IST), but a spokeswoman for the rebels said "the fighting was over".
Ukraine's Prime Minister Arseniy Yatsenyuk, who was in Odessa to observe mourning for the 42 dead, accused Russia of executing a plan "to destroy Ukraine and its statehood".
Several thousand supporters of a united Ukraine, some of them masked and carrying sticks, rallied in Odessa late yesterday before marching to the regional police headquarters.
Demonstrators shouted "Odessa in Ukraine!" and "Glory to Ukraine", also singing the national anthem.
They then peacefully marched to the trade union building to re-deploy the Ukrainian flag that had been burned by supporters of closer ties with Russia Saturday.
Although Moscow has admitted sending troops into Crimea ahead of annexing the strategic peninsula in March, it denies having a hand in Ukraine's unrest in the east. Instead it blames the Kiev government and its Western backers.
In a potentially significant diplomatic move late Sunday, the Kremlin announced that the head of the Organisation for Security and Cooperation in Europe (OSCE), Didier Burkhalter, will visit Moscow Wednesday for talks on the crisis.
The spreading violence eclipsed Saturday's release of seven European OSCE inspectors who had been held for more than week by pro-Russia militants in their eastern bastion of Slavyansk.
The Burkhalter meeting was announced following a phone call between Russian President Vladimir Putin and German Chancellor Angela Merkel, who later said Russia and the OSCE would discuss setting up a national dialogue in Ukraine.
"Putin and Merkel stressed the importance of effective international action - especially by the OSCE - in reducing the tensions in Ukraine," Russia said in its statement.
