KIEV: At least 11 coal miners were killed Thursday when a methane gas blast tore through a pit in western Ukraine, the head of the coal miners' trade union said.
"A methane explosion. 11 killed," Mykhaylo Volynets wrote on Facebook.
Ukraine's emergencies service said that 20 people were unaccounted for and that 172 miners were in the pit at the time.
It added that people were buried under ground after the blast.
Rescue workers were scrambling to the site, in the western Lviv region not far from the Polish border, the emergencies ministry said.
Ukraine has frequent mine accidents that claim dozens of lives each year.
But this is the first major explosion reported this year.
Ukraine relies heavily on coal for electricity and heat despite efforts by Western donors to weaken the former Soviet republic's dependency on the polluting fuel.
Many of the mines are in a dilapidated condition and deemed too dangerous to operate.