A methane leak exploded and killed 12 coal miners in a Polish pit today.

Any hopes for survivors of a deadly mine explosion in Poland vanished today after rescuers recovered the bodies of all 17 men who had been missing, bringing the final death toll to 23.

High levels of gas forced rescuers to suspend their search for 15 miners missing more than a half a mile underground today, and the Polish president said conditions were “getting worse” for anyone trapped and still alive.

Fear of a second gas explosion was slowing efforts to find 15 Polish coal miners missing 3,300 feet underground after a blast that killed at least eight of their colleagues.