Six people were killed on Sunday during a failed rescue attempt at a coal mine in the far northern reaches of Russia, where dozens of workers have been trapped thousands of feet below ground for days after methane gas triggered two explosions there on Thursday.
The six people, including five rescue workers and an employee of the mine, were killed by a third explosion Sunday. Thursday’s explosions killed four miners and trapped 26 people, all of whom are now presumed to be dead.
Combined, 36 people were killed by the explosions, though emergency workers were able to usher 81 other miners to safety before halting rescue operations on Sunday.
“This is a difficult emergency situation, a difficult catastrophe for Russia, for our mining industry,” Deputy Prime Minister Arkady Dvorkovich told Agence France-Presse.
The tragedy took place more than 2,400 feet underground at a mine located in the Arctic Circle in the Russian town of Vorkuta. Officials said heavy smoke, debris and the presence of the methane gas created conditions that hampered the rescue efforts.
Russia’s federal industrial safety monitor, Rostekhnadzor, called the methane leak a natural occurrence.
“According to the materials that have been obtained and preliminary information, the accident had natural causes and was a geological event,” said Alexander Goncharenko, who oversees the regional branch of Rostekhnadzor.
Dvorkovich said the families of the miners who were killed would receive $13,000 in compensation, according to AFP.