Nine workers were killed after an explosion struck a coal mine in Colombia’s Boyaca department on May 5, authorities said.

The blast occurred inside an underground mine near the municipality of Cucunuba, trapping several miners beneath the surface. Rescue teams worked for hours to recover the victims as emergency operations continued overnight. Colombia’s National Mining Agency said the explosion was likely caused by a buildup of methane gas inside the mine, though investigations into the exact cause are ongoing.

Local officials expressed condolences to the families of the victims and called for a review of safety conditions in mining operations across the region. Mining accidents linked to gas buildup and poor ventilation have remained a recurring problem in parts of Colombia’s coal sector.

The country is one of Latin America’s largest coal producers, with thousands of workers employed in underground mining operations, particularly in central regions such as Boyaca and Cundinamarca.