Ukraine says 13 of its servicemen have been killed and 20 wounded in the fighting with Russia-backed separatist forces over the past 24 hours.
The spokesman said the separatists were attacking several villages around Debaltseve.
According to the Polevoi, the fiercest battles were concentrated around the government- held town of Debaltseve, a major railway hub connecting the two main rebel strongholds of Donetsk and Luhansk.
Officials said civilians are being evacuated along the only passable road linking the town to the government side and that conditions are increasingly dire for those left behind.
“People are fleeing because the shelling is non-stop. There`s no water, electricity or heating in the town.” A local police commander Yevgen Lukhaniv told the AFP.
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.
Anti-government protests began in Kieve`s Maidan Square in November 2013 and resulted in the election of a new president and a strongly pro-Western government.