Five workers died after an illegal excavation site collapsed around 4:30 a.m. Sunday in Huize County, Yunnan, trapping six people; the sole survivor was reported in stable condition.
Rescue teams pulled all six from the site and sent them to hospital, where five later died from their injuries, according to Xinhua citing local authorities.
Investigators are now examining the cause of the collapse and potential accountability at the illegal mine.
The deaths sharpen scrutiny of mine safety in China, coming days after a coal-mine gas blast in Shanxi killed at least 82 people.
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