Deadly missile fire has ripped into a government stronghold in eastern Ukraine, in advance of a summit on Wednesday seen as crucial to halting the spiralling conflict.
Fifteen civilians were killed and 63 injured when Russian-backed militants fired a powerful rocket at Kramatorsk, Kiev's military command centre in the largely rebel-held Donetsk region, according to Ukrainian security council chief Oleksandr Turchinov.
The separatists denied the claim and accused government forces of firing on residential areas, as the leaders of Ukraine, Russia, Germany and France prepared to meet in the Belarusian capital Minsk for long-awaited talks.
The shelling of Kramatorsk shook local people and Ukrainian officials, for whom the town was considered safe from attack after government troops retook it last July.
As fighting continued before the planned summit, the volunteer Azov battalion claimed to have forced the insurgents back from the strategic port of Mariupol on the Azov Sea coast of Donetsk region.
“We drove the frontline 20km away from our town, effectively protecting it from artillery strikes and quite strongly reinforcing the defence of this region,” said Mr Turchinov.
The insurgents dismissed his claims as nonsense.
The fighting increased the sense of urgency surrounding the talks and prompted German foreign minister Frank-Walter Steinmeier to express hopes that “no party to the fighting pushes things to the point where an explosion of violence calls Minsk into question”.
‘Political sabotage’
“It wouldn’t be the first time that an act of political sabotage, a targeted strike, destroys all hopes of a ceasefire,” he added.
Fighting since last April has killed more than 5,350 people and displaced more than one million, as Ukraine’s military and Russian-backed rebels have battled over Donetsk and Luhansk regions.
The conflict has dragged relations between Russia and the West to their post-cold war nadir, and prompted warnings of a wider conflict unless these negotiations can, at the very least, help enforce a ceasefire originally agreed upon last September.
French president François Hollande said he and German chancellor Angela Merkel would "be particularly active until the last moment of this meeting so that there can be a deal, a global settlement".
Mr Putin, interviewed by an Egyptian newspaper during a visit to the country, called for a ceasefire but also criticised at the West's treatment of Russia. Ukraine's crisis "emerged in response to the attempts of the US and its western allies who considered themselves 'winners' of the cold war to impose their will everywhere," he said.