Zijin Mining Group Co., China's largest gold producer has shut down a copper smelter in East China after a leakage of acidic water, China National Radio's website cnr.cn reported Tuesday. The company's stock was suspended Monday in Shanghai, but trading resumed Tuesday, and its stock plunged to a 17-month low.

Dead fish lie on the bank of Tingjiang River in Fujian province on July 12, 2010. [Photo/cnr.cn]

The plant in Shanghang county, Fujian province, which produces 12,800 metric tons of copper a year, will only be reopened after checks by local environmental authorities, Lan Fuyan, vice-mayor of Shanghang county, said at a press conference on Monday.

Waste water containing copper and sulfate seeped into the Tingjiang River in Fujian province around 4:00 pm on July 3, and the contamination had been stemmed by 2:30 pm on July 4.

According to initial estimates, the acidic water toxicated and killed more than 1.9 million kg fish, said the report on cnr.cn.