Twin methane gas blasts ripped through Russia's largest coal mine in western Siberia have killed at least 12 workers and injured 41 others. The explosions, one of which occurred last evening and the other this morning, took place in 'Raspadskaya' coal mine in the Siberian region of Kemerovo, about 3,500 kilometres east of Moscow. The fate of 84 people, including 20 rescuers, was unknown as the salvage work had been stopped amid fears of more explosions of methane gas. It was not immediately known what set off the blasts.