A total of 52 dead and 63 injured have been reported so far as a result of the incident, which was caused by the ignition of coal dust in a ventilation duct, after which smoke spread throughout the mine, preliminary investigations indicated.

This Friday the rescue teams took air samples to analyze the risk of explosion in the coal deposit, because yesterday that possibility existed, said the acting Minister of Emergencies, Alexandr Chupriyan, Sputnik news agency reported.

On Thursday morning, at the time of the tragedy, 285 people were inside the mine. Rescuers had to stop the search because of the threat of a new explosion.

The regional authorities reported that most of the miners managed to come out, although 46 workers and six rescuers died in the accident.

Vitali Jeraskov, deputy chief of health of the Russian territory, said that a total of 50 people were taken to hospitals and 13 others were being treated on an outpatient basis.

The report of the spread of smoke and a subsequent explosion in the ventilation shaft of the mine became known at 09:08 local time on Thursday. The smoke occurred at a depth of 250 meters, the Russian Emergency Situations Ministry said.

Three days of mourning were declared in the Siberian region of Kemerovo as of Friday.

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