The Heilongjiang bureau of the National Mine Safety Administration on Friday released the investigation report on the coal mine accident that occurred at the Xing'an coal mine of the Hegang mining company under the Heilongjiang Longmay Group on May 20,2024.The investigation team recommended disciplinary actions for 23 responsible individuals and relevant units,the Xinhua News Agency reported on Friday.

According to the Xinhua report,the investigation concluded that the accident resulted from inadequate fire prevention,and insufficient safety management,leading to a production safety responsibility accident.

On May 20,2024,at approximately 7:52 pm,a carbon dioxide asphyxiation accident occurred at the Xing'an coal mine.After the accident,personnel on site immediately reported to the mine dispatch room and promptly halted the injection operations,actively cooperating with rescue teams to carry out rescue efforts.Four construction workers trapped in the accident tunnel were successfully rescued.By 12:20 am on May 21,the bodies of five deceased individuals had been brought to the surface,marking the conclusion of on-site rescue operations,according to the report.

On May 21,2024,an accident investigation team was established with relevant departments.

The investigation identified that the direct cause of the accident was the unauthorized use of grouting pipes to inject liquid carbon dioxide while addressing natural fire hazards in the mined-out area.The rubber sealing gaskets connecting the pipes became brittle and broke due to low temperatures,leading to a leak of liquid carbon dioxide and the generation of high concentrations of carbon dioxide gas,according to the report.

The investigation team recommended disciplinary actions against 23 responsible individuals and relevant units,and the Heilongjiang provincial commission for discipline inspection and supervision has proposed accountability measures for the involved personnel.

The incident resulted in five fatalities and four injuries,with direct economic losses amounting to 9.59 million yuan($1.34 million),according to a report posted on the website of the National Mine Safety Administration on May 29,2025.