After a mine accident in Poland, two more miners have been found dead.
This increases the death toll to six, said Prime Minister Mateusz Morawiecki on Monday during a visit to the mining rescue center in Bytom.
"This was a black week for Polish mining, for Silesia and for Poland."
After a tremor in the Zofiowka coal mine in Jastrzebie-Zdroj in Upper Silesia, ten miners were missing on Saturday morning.
Four of them were found dead by Sunday afternoon.
The search for the other buried people continues under extreme conditions, said mine director Marcin Golebiowski.
The temperature underground is more than 30 degrees, the methane gas concentration is almost 30 percent.
Only on Wednesday there had been two methane gas explosions in a mine in Silesia belonging to the same company.
Five people were found dead, seven more buried.
The search for them was called off on Friday without result because it had become too dangerous for the rescuers themselves.
A sixth miner died in hospital on Sunday night from severe burns sustained in the blast.