TAIYUAN, May 23 -- An investigation team sent by China's State Council has pledged a rigorous and uncompromising investigation into a deadly coal mine gas explosion in north China's Shanxi Province.

The accident that occurred on Friday in the Liushenyu coal mine in Qinyuan County has left 82 people dead, with nine others still unaccounted for.

The investigation team said it will thoroughly ascertain the cause of the accident, clarify the responsibilities of local authorities, industry regulators and the enterprise involved, and mete out strict penalties in accordance with laws and regulations.

It also urged local authorities to thoroughly overhaul mines' workplace safety, strike hard against illegal and unlawful operations, and crack down upon practices such as falsification of safety monitoring data, unclear headcount of underground personnel, and illegal subcontracting and subleasing.