An explosion at a coal mine in Siberia has left seven dead and at least four injured, Russian media has said.
Emergency officials say that 66 miners are still underground four hours after the deadly blast rocked the mine late on Saturday.
The explosion at the Raspadskaya mine in the Kemorovo region of Siberia is thought to have been caused by a build-up of methane gas in an underground chamber.
More than 300 people were working in the mine at the time of the blast, the Russian Interfax news agency said.
Speaking from Moscow, Al Jazeera's Neave Barker said that the fate of the missing miners was not clear.
"It's not clear if the missing miners are in trouble, but this is not an isolated case. It's not inconceivable that the missing miners are at risk," he said.
In 2007, a blast at the Ulankovskaya coal mine, also in Kemorovo, left more than 100 people dead. In the aftermath of that blast, authorities announced that all surrounding mines would be checked for safety.