Three miners died early on Friday in an accident at the Ziminka mine in the city of Prokopyevsk in southwest Siberia's Kemerovo Region, the regional administration reported.
"The bodies of three miners have been discovered," administration spokesman Anton Gorelkin told RIA Novosti.
There were eight people inside the mine owned by the Siberian Business Union. Five of them survived.
Regional governor Aman Tuleyev established a special commission to investigate the reasons for the methane explosion that killed the miners.