Moscow ? A methane explosion tore through Russia’s largest underground coal mine Saturday, killing 11 workers and injuring 41 others, a regional emergency services ministry official said.

A second blast early this morning forced authorities to halt rescue operations when contact with 20 rescuers was lost, the ITAR-Tass news agency reported.

The second blast destroyed the main air shaft and caused more injuries, and there is a risk of more explosions, Aman Tuleyev, the governor of the west Siberian region of Kemerovo, who is at the site, told reporters.

“The rescue work will continue when the atmosphere in the mine is restored, but to conduct rescue work now means to send people to die,” Tuleyev told ITAR-Tass.