Through high-speed tunneling some 100 cutting faces have been prepared in the first three months of the year.

The Hyongbong, Tokchon and other coal mines belonging to the Tokchon Area Coal Mining Complex have topped their first quarterly target.

The Jenam Coal Mine developed a coal bed with a deposit of much more than one million tons.

The Namdok and Inpho coal mines under the Pukchang Area Coal Mining Complex are surpassing their daily tunneling quotas by employing a rational blasting method.

Coal mines in Sunchon, Anju, Kangdong and Onsong areas have boosted coal output by keeping tunneling ahead of cutting.