A Pit explosion killed at least 46 miners and entombed another 35 in Russia.
Six rescuers sent down into the smoke-filled tunnels to find survivors died hours later.
One miner said those at the centre of the huge explosion were “wiped off the earth”.
Last night hopes of freeing the 35 men trapped 820ft down were fading with rescue teams held back because of explosive methane and poisonous carbon monoxide.
President Vladimir Putin said: “The situation is not getting easier. There’s a danger to rescuers’ lives.
“We’ll hope they can save as many as they can.”
Early reports said the men were in an air pocket beneath the fire at the Listvyazhnaya mine in Belovo, south western Siberia.
PRESS SERVICE OF ADMINISTRATION OF THE GOVERMENT OF KUZBASS/HA/EPA-EFE/REX/Shutterstock)
Before the rescue was halted, regional governor Sergei Tsivilev said there was still electricity and ventilation in the mine but that they had lost contact with people deep underground.
He added: “For now there is no heavy smoke so we hope that there is no fire. The underground communications system is not working.”
Some 285 people were inside the mine 2,000 miles east of Moscow during the blast.
Nikolay Alimov, off work with an injury, said: “Many have been poisoned by carbon monoxide.”
Some miners managed to pull out others “before they suffocated”.
Another pitman said: “I had just started my shift and there was a loud clap.
“There was dust…I started suffocating.”
Last night locals were still praying for a miracle but the situation remained confused. There were also claims of a second explosion 12 hours after the first.
In 2007, over 100 died in a pit blast in the region. In 2010 another 90 died.