A train drives through a tunnel at the Severnaya coal mine in Russia's icy north.

Story highlights

Death toll from a mining accident in northern Russia reaches 36

Explosions in the Servernaya mine in Vorkuta killed 4 and trapped 26 Thursday

Another blast kills 6, including rescuers, and means the trapped miners couldn't have survived

CNN  — 

Russian authorities say the death toll from a mine disaster has risen to 36 after an explosion during an attempt to rescue trapped miners Sunday, according to state-run news agency RIA Novosti.

Sunday’s blast killed six people, including five rescue personnel.

In its wake, Russia’s Emergency Situations Minister Vladimir Puchkov told reporters that there was virtually no chance of survival for any of the 26 miners who had been trapped since Thursday in the Severnaya coal mine in the city of Vorkuta.

Three days of mourning have been declared in Komi Republic, the icy region of Russia’s polar north where the mine is located, Russia state media reported.

The emergency began on Thursday, when two explosions at a depth of 780 meters (about half a mile) ripped through the Severnaya mine, causing a rock collapse and fire. Authorities think the blasts were caused by a sudden leak of methane gas.

Four miners were killed and 81 managed to escape to ground level, authorities say. But 26 remained trapped underground, their fates unknown.

Early Sunday, at 1:24 a.m., a third explosion occurred as a rescue team was attempting to reach the miners, state media reported. The blast killed five rescue workers and a miner.

Puchkov told reporters the blast occurred in the area where the miners were stuck. The high temperatures and lack of oxygen in that part of the mine meant that they had no chance of survival, he said.

Puchkov praised the rescue workers for their bravery.

“They were working under most complex conditions and demonstrated courage, heroism and top-notch skills,” he told reporters.