Ten miners reported missing after an explosion caused by accumulated gas in coal mines in central Colombia have been found dead, raising the death toll to 21, authorities said on Thursday.

The explosion in several adjoining coal mines took place late on Tuesday in a rural area of Sutatausa, about 75 km (46 miles) north of Bogota.

“I have been in communication with Governor Nicolas Garcia, who just informed me that despite all the efforts of rescue teams, unfortunately 21 people lost their lives in the tragic accident in Sutatausa,” President Gustavo Petro said on Twitter.

Every workplace death is not only a failure of companies, but also of society and the government, added Petro, who was elected partly on promises to shift the country from oil and coal, its two top exports, and toward renewable energy.