Local officials in 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 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.