The roof collapse at the Alexeyevsakaya mine near Kemerovo buried a 30-foot section of the coal pit Wednesday, ITAR-Tass reported. All but two of the 107 miners underground at the time escaped unharmed.
Also Friday, Poland offered its help with the search for 24 miners who remained missing after an explosion at the Raspadskaya mine near Mezhdurechensk, RIA Novosti reported. The recovery operation was suspended last week after 66 bodies had been found because of fears of a buildup of methane and the danger of more explosions.
Russian Transportation Minister Igor Levitin and Polish Minister Cezary Grabarczyk discussed the situation at the mine and decided 20 experts from Poland would visit it in early June.
"If Poland has modern technology for protection against methane and other hazards in the mines, then we would ask that they share their expertise with our colleagues from the Ministry of Energy," Levitin said.
Both mines are in the coal-mining region around Kemerovo in western Siberia.