A Siberian mining region began three days of mourning on Friday after more than 50 people died in a coal mine accident and a rescue effort that ended in tragedy.
After initially reporting that six rescuers had died during attempts to reach miners, officials said Friday that one had been found alive and taken to hospital for treatment.
But news of his survival was a small consolation for a community devastated by the loss of 51 lives, including those of 46 miners, in the worst mining accident in Russia in more than a decade.
Officials said it appeared Thursday's accident at the Listvyazhnaya mine in the Kemerovo region had been caused by a methane explosion.
Investigators launched a series of probes into possible safety violations, with senior managers at the facility arrested.
Flags flew at half-mast outside official buildings in Kemerovo and grief-stricken relatives of the victims wept outside the snow-covered mine site.
"I can't carry on," one woman said, as families gathered in sub-zero temperatures.
A former worker at the mine, Denis Timokhin, told independent TV channel Dozhd safety violations wee frequent at the facility, accusing management of forcing miners to work despite high methane concentrations.
"If you don't want to work, quit," he said. "No safety protocols, all sensors are plugged with bags."
- Rescuer's 'miracle' survival -
Accidents are a part of life in the mining region, and some residents in the village of Gramoteino next to the mine laid flowers at a memorial dedicated to rescuers killed in a previous mine accident in 2000.
Officials said the Listvyazhnaya mine filled with smoke on Thursday morning after the apparent explosion, with 285 people underground.
Miners described a frantic scramble to evacuate.
"I stretched out my hands, they couldn't find me on their own, because the visibility was bad," another said. "They grabbed me... I didn't understand who it was and where they were pulling me."
A search and rescue operation launched on Thursday had to be temporarily called off because of fears of another explosion.
Six rescuers went missing and were believed dead until medic Alexander Zakovryashin was found alive on Friday.
Regional authorities said he had spent the night in the mine and managed to get to the surface and call for help.
Acting emergencies minister Alexander Chupriyan called his survival "a miracle" and paid tribute to those who had died.
"This is a huge tragedy for the entire country and the Russian emergencies ministry," Chupriyan said.
"Rescuers, just like miners, did their duty to the end," he said, and their names "will remain forever in our memory."
Zakovryashin and his five dead colleagues were to be awarded the Order of Courage, one of Russia's top honours, the ministry said.
Nearly 50 people were hospitalised following the accident, regional authorities said.
Safety probes launched
Russia's Investigative Committee, which probes major crimes, opened a criminal case and said three people had been detained on Thursday including the director of the mine and his first deputy.
"During the initial investigation, it was established that the detainees violated industrial safety requirements," the committee said.
On Friday, investigators opened another probe against two officials of the local branch of state safety watchdog Rostekhnadzor, accusing them of failing to conduct proper inspections of the mine.
The governor said officials launched checks at all mines in the region.
Mining accidents are fairly common in Russia as a result of poor safety standards, a lack of oversight of working conditions and ageing Soviet-era equipment.
The Listvyazhnaya mine, near the town of Belovo, was set up in 1956 and is owned by the SDS-Ugol company based in the city of Kemerovo.
A methane blast in 2004 killed 13 people at the mine and another explosion at the site killed five people in 1981.
One of the deadliest mining accidents in Russia in recent years occurred at the Raspadskaya mine in Siberia -- Russia's largest coal mine -- in the summer of 2010, killing 91 people and leaving more than 100 injured.
In 2007, 110 people died after a gas explosion at the Ulyanovskaya mine, in the same region.