KIEV, Ukraine — Russian-backed separatists kept up their assault Sunday on railway hub in eastern Ukraine, fighting that authorities said has killed 13 government troops and wounded 20 others over the last day.
The separatists were attacking several villages around the town of Debaltseve, a key rail link between the two rebel strongholds of Donetsk and Luhansk, Security Council spokesman Vladimir Polevoi said. Capturing the town would further consolidate the rebels' control over eastern Ukraine.
An Associated Press journalist saw more than a dozen Ukrainian tanks and other heavy military vehicles, including a rocket launcher, heading toward Debaltseve on Sunday in an apparent effort to reinforce the government troops.
There was no word on any rebel casualties.
Seeking safety from the intense artillery duel, hundreds of Debaltseve residents have fled the besieged town, which has been without power, water and gas for more than 10 days.
About 60 Debaltseve residents arrived Sunday in Kiev, the capital, where they took part in a protest outside the Russian Embassy. An adjacent garden was turned into a symbolic cemetery, with wooden crosses erected in memory of the 30 civilians killed by shelling in the southeastern city of Mariupol in late January. Plaques on the crosses said they were "killed by Russian occupiers."
"Russia is conducting an undeclared war in Ukraine," said Yevgeny Chebotarev, who met the people arriving by train from Debaltseve and was helping them find shelter. "Today it is obvious that behind the DNR and LNR (the Donetsk and Luhansk self-proclaimed republics) stand Russian troops and Russian weapons, whose victims are Ukrainian civilians."
Russia denies sending arms and troops to the rebels, who claim to rely solely on military equipment poached from the Ukrainian army. But the separatist forces have deployed vast quantities of powerful weapons, some of which military experts say are not in Ukraine's arsenal.
The conflict has claimed more than 5,100 lives and displaced more than 900,000 people since it began in April, according to U.N. estimates.
A month of relative quiet in eastern Ukraine was shattered in early January by full-blown fighting as the separatists attempted to claw back additional territory from the government. Rebel leaders accused Ukraine of mobilizing forces in advance of an offensive.
Representatives for the rebels, Russia, Ukraine and the Organization for Security and Cooperation in Europe met Saturday for four hours in Minsk, the capital of Belarus, but failed to make any progress toward a peaceful resolution.
Peter Leonard in Artemivsk, Ukraine, contributed to this report.