Government forces and Russian-backed separatists have been exchanging mortar and rocket fire around the flashpoint eastern town of Avdiivka that sits just north of the Russian-backed rebels' de facto capital of Donetsk.
The surge in clashes since Sunday have claimed the lives of at least 20 people and reignited fears of full-scale warfare returning to Ukraine after a relative lull in 33 months of bloodshed in the European Union's backyard.
The Avdiivka shelling left more than 20,000 people without heat or water in freezing winter weather and authorities scrambling to provide relief.
The fighting comes at a potential watershed moment for Ukraine because fears are mounting in Kiev that staunch US support could wane with President Donald Trump looking to mend ties with Russian counterpart Vladimir Putin.
Moscow and Kiev have traded blame over who started the latest violence but AFP reporters witnessed the rebels on the attack.
Kiev worries that Putin is trying to stamp his authority on eastern Ukraine to give him leverage over Trump on other global issues.
NATO chief Jens Stoltenberg did not blame Russia directly but said that Moscow had ‘considerable influence’ over the militia forces now on the attack.
‘We call on Russia to use its considerable influence with the rebels to bring the violence to an end,’ Stoltenberg told reporters in Brussels on Wednesday.
The escalation in violence has also refocused world leaders' attention on a conflict that had slipped from focus despite claiming the lives of more than 10,000 people.
- Mortars and gruel -
Thursday morning began with echoes of rocket fire on the blue-collar town's outskirts and the death of a woman in a shelling attack.
‘Three men were also injured,’ pro-Kiev Donetsk regional police chief Vyacheslav Abroskin wrote on Facebook.
‘There were several attacks on our positions overnight that were all repelled,’ the Ukrainian army's 72 brigade spokeswoman Olena Mokrynchuk told AFP.
‘There is no lighting in the city and we are keeping the local heating plant at the lowest temperature possible that would avoid its pipes from freezing,’ she said.
Army officers were distributing gruel and tea to hundreds of people in makeshift street kitchens as the echoes of exploding shells reverberated.
They also set up seven camps where people could warm up from winter weather that sees temperatures fall to minus 20 degrees Celsius (minus four degrees Fahrenheit) at night.
‘Right now we are making buckwheat and millet porridge,’ said a 40-year-old serviceman who gave his name only as Taras.
‘We hope to get some canned meat in the evening,’ he told AFP.
- Why Avdiivka? -
The industrial town was seized by separatists when the conflict started in April 2014 after the ouster of Ukraine's pro-Russian leader but was recaptured by Kiev several months later.
Ukraine has a large military presence nearby and in surrounding towns that are one the main hotspots of the fighting.
It has a giant coke plant that produces natural gas for generating heat and electricity and also has important roads used by the separatist fighters to move around machinery and weapons.
Russia denies accusations from Kiev and its allies that it sparked the war in a bid to keep Ukraine under its thumb after its tilt towards the West.
