171 miners were trapped in a flooded coal mine in east China's Shandong Province, reports said on Saturday.
The flooding occurred at about 2:30 pm on Friday (1200 hrs IST) at the Zhangzhuang mine located in Xintai City in the central part of the province.
"There were 756 miners working under the ground when the accident occurred. By Friday night, 584 miners have been rescued," deputy secretary-general of the provincial government, Zhang Dekuan who is at the site, said.
The provincial government has established a rescue headquarter at the site.
Heavy rain is pouring down at the site making the rescue operations difficult, Xinhua news agency reported.
The cause of the accident is still under investigation.
China's coal mines are notorious for their high accident rates.
A total of 1,792 coal miners died in 1,066 mishaps in China, the world's top coal producer and consumer, during the first half (January-June) of this year.
In 2006, coal mine accidents killed 4,746 people in China in 2006 with an average of 13 deaths per day.