Twenty-three people have been held accountable for a carbon dioxide asphyxiation accident at a coal mine in Hegang, Heilongjiang province, on May 20, 2024, according to a statement released by the National Mine Safety Administration on Friday.

The accident occurred at the Xing'an Coal Mine, killing five people and injuring four. It led to direct economic losses of more than 9.5 million yuan ($1.3 million).

Investigators found that the accident was the result of a failure to implement fire prevention measures and inadequate safety management.

READ MORE: Five dead in coal mine accident in Northeast China

The report also mentioned that workers improperly used liquid carbon dioxide to try putting out a fire in the collapsed mining area without authorization, which indirectly contributed to the incident.

The pipeline connections' sealing rubber gaskets became brittle and damaged, leading to the leakage of high-concentration carbon dioxide gas, causing suffocation casualties among the workers in the pre-closed track tunnel of the retreat working face.

The 23 responsible people and units have received various punishments, including fines or disciplinary actions within the Party, revocation of relevant qualifications.

READ MORE: 43 held accountable in Heilongjiang coal mine incident

Xing'an Coal Mine was fined 1.85 million yuan and had its safety production license temporarily suspended.