Russian forces late on Friday attacked the town of Dobropillia in eastern Ukraine, killing at least four people and injuring 18.

Regional Governor Vadym Filashkin, writing on the Telegram messaging app, said Russian forces launched three night-time strikes on the town north of Pokrovsk, one of the focal points of their advance through eastern Ukraine.

Filashkin initially said five people had died in Dobropillia.

It was gathered that Donetsk region is the theatre of the fiercest fighting in the three-year-old war against Russia, with Moscow’s forces advancing slowly and steadily westward as part of a drive to capture the Donbas, made up of Donetsk and Luhansk regions.

Filashkin said that according to initial information, four high-rise apartment buildings were damaged in the assault, adding that emergency crews were at the site.

The regional governor urged residents of towns near the 1,000-km (620-mile) frontline of the war to evacuate their homes in good time.

Meanwhile, Donetsk prosecutors had earlier said five residents of the region had been killed in Russian attacks on a string of towns and villages.

In Ukraine’s southern Black Sea port of Odesa, Regional Governor Oleh Kiper said a Russian drone attack had again damaged energy infrastructure and other targets.

Drones have attacked the city for several consecutive nights.

War: Four killed, 18 injured in Russian drone attack on Ukraine