A string of explosions at a Russian coal mine just inside the Arctic Circle has killed 36 people — miners trapped inside as well as rescue workers trying to help them, officials say. When the blasts hit last week, they caused a rock collapse and a fire that is still burning.

Occurring over several days, the explosions are being blamed on a buildup of methane gas. When the first one shook the Severnaya mine in the Komi Republic in northwest Russia, 111 miners were underground, according to the state Tass news agency. In the hours that followed, officials say, 81 miners were able to reach safety and the bodies of four of miners were recovered.

A strong explosion hit during a rescue operation Sunday, killing a mine employee and a five-member rescue team.

After an initial period of uncertainty and hope for the remaining 26 miners' survival, officials now say they believe those miners have also perished.

"We have to state that all the parameters that have evolved at the accident-hit section of the coalmine do not allow anyone to survive," Russian Emergencies Minister Vladimir Puchkov says, sharing his agency's analysis of conditions in the mine.

Federal investigators are now looking into how the disaster happened. According to Puchkov, the mine in the town of Vorkuta isn't likely to be declared stable until a least a month from now.

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