Local officials in North China's Shanxi province said on Saturday night that a preliminary investigation had found major legal violations by the coal mine company involved in a Friday gas explosion that killed at least 82 people.

The explosion occurred at the Liushenyu coal mine in Qinyuan county, Changzhi city, North China's Shanxi province. The mine is operated by Shanxi Tongzhou Group, a local private enterprise.

Changzhi Mayor Chen Xiangyang said at a news conference in Qinyuan on Saturday night that the company's actual controllers, persons in charge and other relevant personnel had been taken into custody in accordance with the law. He added that the specific cause of the accident remains under investigation.

As of around 10 pm on Saturday, the accident had killed 82 people, with two others still missing, Chen said. A total of 128 injured people were receiving treatment in hospitals, while 35 others who were uninjured had returned home on their own.

The mayor apologized to the public, as well as to the victims, the injured and their families, and expressed deep condolences to those who lost their lives in the accident.

Guo Junzhi, head of the health commission of Changzhi city, said all 128 people injured are now in stable condition, including four patients who were previously in serious or critical condition. 

The 124 patients with mild injuries had been transferred to tertiary hospitals for observation and treatment, according to Guo.

He said the two severe patients and two critical cases have each received targeted treatment plans developed by dedicated expert teams to reduce the risk of mortality, and all four are now in stable condition with no life-threatening risks.

Guo Xiaofang, head of the Qinyuan county government, also apologized at the news conference, saying that chaotic conditions at the scene and the company's unclear count of workers on duty had led to inaccurate initial figures.

"This accident caused heavy casualties. It is extremely serious in nature and the lesson is painfully profound," Chen said.

He said authorities would spare no effort and no cost in searching for the missing, while doing everything possible to treat the injured.

The investigation would be carried out in a fact-based and scientific manner to further determine the cause of the accident, Chen said.

"We must give the victims, their families and the public a responsible explanation," he said.

Guo said the accident had exposed "serious loopholes and weaknesses" in key areas of local governance, including workplace safety supervision, the identification and rectification of risks and hidden dangers, and the fulfillment of companies' primary responsibilities.

He said the next phase of work would focus on verifying information, communicating with families of the dead and injured, handling compensation, meeting families' daily needs, and conducting forensic examinations.

Authorities will carefully verify the identities, backgrounds, family relationships and household conditions of the dead and injured to ensure the accuracy of information, Guo said.

They will also immediately provide emotional support and psychological counseling to family members, and steadily advance the calculation, negotiation and payment of compensation, he said.

Special attention will be given to helping elderly people living alone, the weak, the sick, families in difficulty and other vulnerable relatives, Guo said.

'Tough and uncompromising' probe

A "tough and uncompromising" investigation will be carried out by the State Council, China's Cabinet, into the gas explosion, Xinhua News Agency reported on Saturday evening.

The accident investigation team will make rigorous efforts to determine the cause of the accident, clarify responsibilities in local management, industry supervision and corporate operations, and impose strict penalties in accordance with laws and regulations, according to the Xinhua report.

All regions and relevant departments have been urged to conduct a comprehensive review of the implementation of mine safety measures and to crack down hard on illegal and rule-breaking operations, it said.

Authorities were also required to carry out strict investigations and impose punishments over problems including concealed working faces in coal mines, falsification of safety monitoring data, unclear numbers of underground workers, and illegal subcontracting or contract transfers, according to the report.

Meanwhile, Vice-Premier Zhang Guoqing called for all-out search and rescue efforts and a thorough investigation into the cause of the explosion.

Zhang, who is also a member of the Political Bureau of the Communist Party of China Central Committee, urged further safety inspections and rectification in key sectors across the country, including coal mines and hazardous chemicals, according to China Media Group.

The senior official led a working group to the site of the gas explosion on Saturday to guide emergency response work.

He convened a meeting at the on-site command center to arrange work on rescue and medical treatment, victim support and aftermath handling, and accident investigation.

Zhang stressed the need to mobilize professional forces to carry out scientific search and rescue operations with all-out efforts, while preventing secondary casualties. The number of missing people must be verified, and no one should be left unaccounted for, he said.

He also called for organizing high-level medical experts to provide careful treatment for the injured and minimize disabilities caused by injuries.

Medical response

Also on Saturday, the National Health Commission said it has organized health officials and multidisciplinary medical experts to guide treatment for people injured in the blast.

Senior officials from the commission have been dispatched to guide on-site rescue and medical treatment efforts.

Three medical specialists in respiratory and intensive care, burns, and orthopedic trauma from Peking Union Medical College Hospital and Beijing Jishuitan Hospital have also been sent to provide on-the-ground medical support.

Experts from leading hospitals specializing in trauma care, intensive care and respiratory care have been mobilized to provide remote consultations.