Six Ukrainians died in a Saturday coal-mine blast, the Interfax news agency reported.
The explosion resulting from a methane gas build-up took place in the Duvana shaft near the city of Sukhodolsk, in the eastern Luhansk province, reproted dpa.
An evacuation of the surviving 113 miners from 550 metres below ground was completed without incident.
An investigation into possible violations of safety procedures was in progress, Vice Prime Minister Oleksander Turchinov said.
The government would provide financial assistance to the victims' families, he said.
Ukraine's coal mines are among the world's most dangerous, with on average one miner losing his life on the job for every million tons of coal brought out of the ground.
A traditionally lackadaisical attitude towards mine safety and high demand for coal contributes to the death rate.