Moscow ? Rescuers pumped fresh air into the smoke-choked shafts of a Siberian gold mine Friday, hoping that 21 miners were still alive a day after a fire killed at least 12 workers in Russia’s latest mining disaster.

Thirty-one miners made it to the surface Thursday within hours after the blaze broke out in the 105-year-old mine, said Emergency Situations Ministry spokeswoman Yulia Stadnikova.

Emergency workers later recovered the bodies of the 12 miners, leaving 21 men still in the Darasun mine in the Chita region some 3,000 miles east of Moscow, state safety watchdog Rostekhnadzor said.

Stadnikova said the fire, which erupted at a depth of between 280 feet and 430 feet, was still burning and smoke hampered rescue efforts.