Russian-backed rebels in eastern Ukraine have accused Kyiv government forces of shelling a village with artillery, the Interfax news agency reports.
Kyiv and the rebels blamed each other for escalating tensions after artillery and mortar attacks on Thursday, prompting fears that Russia, which has massed over 100,000 troops near Ukrane's borders, could get involved.
The Kremlin said on Thursday it was "deeply concerned" with the flare-up in Ukraine and was watching the situation closely.
According to the Interfax report, the self-proclaimed Donetsk People's Republic said the shelling targeted the Petrivske village in the breakaway region at 5.30am on Friday.
Kyiv and the pro-Russian separatists have been at war for eight years and the ceasefire between the sides is routinely violated, but the intensity of fighting increased notably this week.Â