Ukraine said Thursday that Russian shelling had left three people dead and several more injured at mining facilities in Toretsk, a town in the war-battered eastern Donetsk region.
The region has seen the brunt of fighting of Russia's nearly two-year invasion, and the Kremlin claimed to have annexed it along with three other eastern and southern territories last year.
"Two bombs hit the territory of one of the mines in Toretsk. One person was killed and two others were injured," Interior Minister Igor Klymenko said in a statement on social media.
"Two more bombs hit the territory of another mine. Two people were killed and three were injured," he added.
He said that the first mine hit had been cut off from electricity and that 32 miners who were underground at the time of the attack had been brought to the surface.
Klymenko added that the Russian strikes damaged administrative buildings and equipment at the mine, and police were investigating the incident.
Parts of Donetsk, a region known for its coal mines, have been partially controlled by Russian forces or their proxies since 2014.
Prior to Russia's invasion, Toretsk had a population of around 31,000 people. It lies north of the town of Avdiivka, a hotspot of fighting in the east which Russian forces are attempting to encircle.