The Russian-backed head of part of Ukraine's Donetsk region controlled by Moscow's forces on Monday accused Ukrainian forces of injuring 20 civilians in shelling of the town of Volnovakha and of killing a six year-old girl with a mine.

Reuters could not verify the assertions by the official, Denis Pushilin, and there was no immediate comment from Ukraine on his allegations.

In a statement posted on the Telegram messenger app, Pushilin said that Ukraine had struck "a lively and absolutely civilian" area of Volnovakha using Western-supplied rocket systems.

The six year-old girl had been killed in the Volnovakha area, he said, when a Ukrainian mine struck the courtyard of her home. Russian-installed police officials in the area said the mine was one of many dropped by parachute by Ukrainian forces in recent days.

Volnovakha, which had a population of around 21,000 before the start of what Moscow calls its "special military operation," was taken control of by Russian forces shortly after tens of thousands of Russian troops swept into Ukraine in February last year.

It remains close to the areas of the frontline where Kyiv has focused its counteroffensive.