Six dead in mine blast in Kazakhstan
Sixty-four workers were in the mine at the time of the accident, and 56 were able to get out.
"Six people died (and) two were injured," the emergencies ministry said in a statement.
ArcelorMittal said the accident had taken place due to an "outburst" of gas and coal.
The company said the two injured workers were in "critical condition."
A government commission headed by Emergencies Minister Yury Ilyin was dispatched to the scene.
Mining accidents are fairly common in former Soviet countries due to lax safety practices and outdated infrastructure.