Among miners killed in a methane blast near the town of Karvina are 11 Polish nationals and two Czechs.

A methane explosion in a Czech coal mine has killed 13 miners, including 11 Polish nationals and two Czechs, the mine operator OKD said on Friday.

The state-run OKD company said a methane blast more than 800 metres (875 yards) underground devastated areas of the CSM hard-coal mine, near the town of Karvina, on Thursday.

“Due to yesterday’s mine disaster, 13 miners lost their lives – 11 Poles and two Czechs,” OKD spokesman Ivo Celechovsky said at a televised news conference.

The incident is the worst mining accident in the Czech Republic since 1990, when 30 miners died in a fire at a mine near Karvina, according to a list compiled by the CTK news agency.

OKD said most of the victims and injured were Polish miners provided by the ALPEX company.

OKD managing director Boleslav Kowalczyk said the search of the scene had had to be abandoned due to conditions in the shaft.

“Unfortunately, we have reached a point where it was impossible to move forward because there was a fire raging and zero visibility,” he said.