Qinyuan County, CHINA – A deadly gas explosion tore through a coal mine in northern China’s Shanxi province on Friday, killing at least 82 people in the country’s worst mining disaster in nearly two decades.

The blast struck the Liushenyu shaft whilst 247 workers were underground. Rescuers were searching on Sunday for two people still missing, with helmeted teams taking turns descending into the shaft overnight and sending down a robot to probe the mine conditions.

“As long as there is hope, we will make every possible effort,” one rescuer told state media.

Hundreds of rescuers rushed to the site after the explosion, with medical teams taking 128 people to hospital as of Saturday evening, loaded into ambulances and carried on stretchers.

Chinese authorities launched an investigation into the blast, with preliminary findings showing that Tongzhou Group, the company operating the mine, had committed “serious illegal violations”. More than half of the workers in the shaft on Friday had gone down without being properly registered, state media said, citing a personnel board at the site. Miners are normally required to undergo facial recognition checks or take location-tracking cards before their descent.

“Those found responsible will be severely punished in accordance with laws and regulations,” officials said at a news conference. A person “responsible for” the company had been “placed under control in accordance with the law”, state media reported.

Anxious family members gathered at a checkpoint near the mine on Sunday, hoping for information about their loved ones. Police monitored the area closely, preventing relatives from reaching the site.

Injured survivor Wang Yong told state television he heard nothing but smelled sulphur when the explosion happened.

He recalled seeing people choked by the smoke before he fainted, regaining consciousness after more than an hour.

The blast is the worst since 2009, when 108 people were killed in a mine explosion in north-eastern Heilongjiang province. China’s State Council ordered nationwide “tough crackdowns on illegal and unlawful activities”, including the falsification of safety data, unclear headcounts of underground workers and illegal contracting.

Foreign leaders extended condolences, with Japanese Prime Minister Sanae Takaichi saying she was “praying for the rescue of as many people as possible”.

Shanxi, one of China’s poorer provinces, is the centre of the country’s coal-mining industry. Whilst mine safety has improved in recent decades, accidents still occur in an industry where safety protocols are often lax and regulations vague.