SUTATAUSA — An explosion at the Carbonera Los Pinos coal mine in Sutatausa, in Colombia's Cundinamarca department, killed nine miners and injured six on Monday. Fifteen miners were inside the shaft, located about 50 miles (80 kilometers) north of Bogota, when the blast occurred at least 600 meters underground.

Three of the miners escaped on their own, and the remaining three survivors were rescued. The six injured miners were taken to a local hospital for treatment, where they were recovering. Rescue workers traveled to the site, with images shared of ambulances at the mine's entrance, while authorities assessed gas levels in the mine before conducting further rescue operations.

The blast was caused by a buildup of gases, according to the National Mining Agency. The mine was legally operated.

Cundinamarca provincial governor Jorge Emilio Rey wrote on X that the explosion was "apparently due to a buildup of gases." In a separate post, Rey said, "We deeply regret this tragedy and send a message of condolence, solidarity, and support to their families."

Colombia's National Agency for Mining inspected the Carbonera Los Pinos mine in early April and recommended sealing off areas no longer used for coal extraction due to potentially dangerous accumulation of gases including methane. The agency did not say whether its recommendation had been implemented.

In a statement following the explosion, the National Mining Agency said, "As the ANM has warned during its inspection visits, coal deposits can present accumulations of gases such as methane, as well as concentrations of coal dust." The agency also said it "expresses its solidarity with the families of the victims and regrets this mining accident in which, thanks to timely rescue efforts, six miners were rescued alive."

Mining accidents are common in central Colombia, where dozens of small operators run coal and emerald mines. In 2023, 11 miners were killed by an explosion at another coal mine in Sutatausa. In 2020, 11 miners died during a mining accident in Cucunuba, another municipality in Cundinamarca province.