A deadly mine accident in northern China is casting a spotlight on the dangers inherent in the country’s effort to prioritize energy security by boosting coal production.

At least six people are dead and 47 missing after a wall collapsed at Xinjing Coal Industry Co.’s open-pit mine in a remote part of Inner Mongolia. Police are investigating the cause of the disaster and have detained several people suspected for being responsible, state broadcaster CCTV reported. 

According to Fengkuang Coal Logistics, the mine in question has a history of safety violations and was shut down for three years before 2021, when government officials gave the company permission to reopen it and convert it from a below-ground to an open-pit operation.

That year, China began a campaign to boost coal production after a shortage of the fuel caused widespread power outages. The efforts paid off, with production jumping 10% last year and China getting through the winter without supply disruptions and with ample stockpiles. 

But even at the time, industry executives warned that the push to produce more would likely cost lives as companies reopened and expanded smaller mines that, prior to the crisis, had been deemed unnecessary.

Xinjing Coal didn’t respond to a request for comment sent to its public email address.

Among the safety problems at the Xinjing mine, it faced administrative punishment for not having signs for speed limits and crossings on the main road to the pit, and for failing to have a warning sign in a landslide area, according to Fengkuang. It was forced to stop production in 2015 for not receiving approval to begin construction and for not implementing environmental impact assessment requirements, the consultancy said.

As rescue crews continue their search for the remaining missing workers, government officials in Inner Mongolia and neighboring provinces have launched safety inspections to try to prevent more accidents. That may slow production in the first quarter, but the impact is likely to be limited as Beijing continues to prioritize producing enough coal to fuel its economic rebound, according to a note from Citic Futures Co.