The death toll in Russia's worst mining disaster in recent history climbed to 36 on Sunday as officials said 26 missing workers had not survived and another six, most of them rescuers, had been killed in a new explosion.
On Thursday, four miners were killed when a methane explosion ripped through the Severnaya mine in Arctic Russia at a depth of 748 metres (2,450 feet).
Tatyana Bushkova, a spokeswoman for the mine's operator Vorkutaugol, told AFP in an emailed statement Sunday that "according to the expert technical council, 26 (missing) people who were in the mine had no chances of surviving."
"The rescue operation has been halted," she said.
A fresh methane explosion at the mine early Sunday killed five rescue workers and a miner, Anton Kovalishin, a spokesman for the emergencies ministry in the Komi region where the mine is located, told AFP.
The pit is located in the city of Vorkuta in the Komi region, which used to host one of the most feared Soviet-era Gulag labour camps.
Vorkutaugol is operated by Severstal, the Russian steelmaker controlled by billionaire Alexey Mordashov.
Authorities launched a massive search operation involving hundreds of rescue workers who had been trying to track down the missing despite almost zero visibility, smoke, gas-polluted air and rubble.
Both the company and authorities had until now refused to declare the missing dead even though rescuers appear to have failed to make contact with them over the past few days.