Russia’s coal mining sector has been trying to improve its safety record.

An underground explosion at a coal mine in the Komi region of northern Russia has killed at least nine miners, officials say.

Rescuers are searching for eight others feared trapped underground. About 250 miners escaped to the surface.

The explosion at the Vorkutinskaya mine is thought to have been the result of a methane gas build-up.

Accidents are frequent in Russia’s huge coal mining industry despite recent efforts to improve safety.

The coal mine outside the city of Vorkuta in the Russian Arctic is operated by the steel-making giant Severstal.