The gas explosion occurred late on Friday at the Liushenyu coal mine in Qinyuan county, with 247 workers on ​duty underground, state media Xinhua reported earlier in ​the day.

Chinese President Xi Jinping called for authorities to “spare ⁠no effort” in treating the injured and conducting ​search and rescue operations, while ordering a thorough investigation into ​the cause of the accident and strict accountability in accordance with the law, according to Xinhua.

Premier Li Qiang echoed the instructions, calling ​for the timely and accurate release of information and rigorous ​accountability.

Rescue operations were ongoing, and the cause of the accident was ‌under ⁠investigation, according to the local emergency management authority in Qinyuan.

China has significantly reduced coal mine fatalities — often caused by gas explosions or flooding — since the early 2000s through ​more stringent regulations ​and safer ⁠practices.

The Liushenyu incident, though, was one of the deadliest reported in China in ​the past decade.

Executives of the company responsible ​for the ⁠mine have been detained, Xinhua reported.

Earlier, Xinhua had reported only eight dead, with more than 200 people brought safely ⁠to ​the surface. It did not explain ​the jump in the death toll.