BEIJING (AP) — A gas explosion at a coal mine in China's northern Shanxi province killed at least 90 people, state media said on Saturday. It was the country's deadliest mining accident in recent years.

The official Xinhua News Agency said the accident at Changzhi city's Liushenyu coal mine happened on Friday evening. Around 247 workers were on duty at the time.

Nine miners were still unaccounted for as of Saturday afternoon, Xinhua said, and more than 120 people were hospitalized.

The cause of the explosion was under investigation, Xinhua reported, and rescue work is pressing on with hundreds of rescuers and medical personnel sent to the site. Among the injured, many were hurt by toxic gas, according to state broadcaster CCTV.

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Chinese President Xi Jinping has called for an all-out effort to rescue the missing, Xinhua reported. Xi also called for the "proper handling of the aftermath of the accident and urged a thorough investigation into its cause, with accountability pursued in accordance with the law."

Xinhua later reported that those responsible for the company involved in the mine accident have been "placed under control," citing the local emergency management bureau.

An investigation team sent by China's powerful State Council, equivalent to the country's cabinet, would be conducting a "rigorous and uncompromising" probe into the deadly explosion, a separate Xinhua report said following Xi's remarks.

Wang Yong, one of the hospitalized miners, told CCTV in a video interview that he smelled sulfur "like firecrackers" and saw smoke. "I told people to run," he said. "As I ran, I saw people being choked by the smoke. And then I blacked out."

The state broadcaster also reported that blueprints provided by the coal mine did not match the actual layout, hampering rescue efforts.

The coal mine, operated by the Shanxi Tongzhou Coal & Coke Group with an annual production capacity of 1.2 million tons, was placed on a national list of disaster-prone coal mines by China's National Mine Safety Administration in 2024 for having "high gas content."

Shanxi province is known as China's main coal mining province. With a size larger than Greece and a population of around 34 million, the province's hundreds of thousands of miners dug 1.3 billion tons of coal last year, almost a third of China's total.

In China, coal remains a key energy source due to its lower cost and high availability, even as the country accelerates its transition toward green energy. Mining disasters have been common although authorities had implemented measures to improve safety over the past years.

In February 2023, 53 people were killed after a collapse at an open-pit mine in northern China's Inner Mongolia region. In November 2009, an explosion at a mine in northeastern China's Heilongjiang province killed 108, according to state media.