"Today, five people were killed after Russian shelling in the region of Donetsk," the Donetsk governor Pavlo Kyrylenko posted on Telegram.

Four of them died in the city of Vugledar, and one in the town of Novomikhaylovka, he added.

The fighting has become increasingly fierce in the region, where authorities have urged residents to evacuate before a feared Russian offensive.

On Saturday, the Ukrainian army announced on Facebook that it had "destroyed four tanks, eight armoured vehicles and seven enemy vehicles", as well as "a plane, a helicopter" and drones.

Further north, in the Kharkiv region, "at least two people were killed in Slatyne as a result of a (Russian) shelling and another injured", mayor of the neighbouring municipality of Dergachi, Vyacheslav Zadorenko, wrote on Facebook.