BEIJING (AP) — Rescuers in southern China are struggling to pump water from a coal mine where 22 miners have been trapped for more than a day.

State media say narrow passageways and a lack of electricity at the Xiahaizi mine in Yunnan province were hampering efforts Tuesday.

The Xinhua News Agency said four miners escaped following the shaft’s flooding before dawn Monday, which was apparently caused by blasting on an upper level. No information was given about the condition of the men still inside.

Xinhua said more than 500 people and three high-powered pumps were sent to the mine in Qujing city’s Qilin district, with more rescuers, pumps and electrical systems on their way.

China’s mines are notoriously deadly, although safety improvements in recent years have significantly reduced the deaths.

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