At least 1,890 tons of fish were poisoned in a recent sewage leakage from a copper mine in east China's Fujian Province.

Dead fish lie on the bank of the Tingjiang River in Shanghang county, Fujian Province, the result of sewage leaking into the river since July 3 from the local Zijinshan Copper Mine. [Xinhua]

On Monday, the Fujian environmental authorities confirmed that a sewage leakage from the Zijinshan Copper Mine had caused serious pollution in the Tingjiang River, one of the largest waterways in Fujian.

The provincial government sent a work group to further investigate the contaminated area.

The Shanghang county government and the Zijinshan Copper Mine had reached an agreement for the company to buy the fish at 12 yuan a kg and to buy tiddlers at 24 yuan a kg in the affected area.

The company was also putting lime into the river to neutralize the acid in the water. So far, no personal injuries have been reported as a result of the water pollution.

The leakage occurred on July 3 when an employee of the Zijinshan Copper Mine discovered the water level had dropped in the sewage lagoon. It has since been established that an "impermeable membrane" used to line the pool had become damaged over time.

The sewage that leaked contained "copper iron but no extremely toxic substances," according to the Zijin Mining Group, the country's largest mining company, which owns the copper mine.

The Hong Kong-listed Zijin Mining Group (ZMG), announced on Monday that it would suspend its stock as of 9:30 on Monday morning.

This was not the first incident of its kind for ZMG. According to a report in the Century Weekly, the local education bureau of Shanghang county issued a notice warning students "not to eat fish" before the National College Entrance Examination, which began on June 7.

According to the report, a reservoir of ore waste owned by the ZMG had leaked heavy metal into the Tingjiang River, causing a massive loss of fish.

The Ministry of Environmental Protection issued a notice in May that criticized 11 enterprises for failing to protect the environment. ZMG ranked first on the list.

In its notice the ministry had also ordered six companies owned by ZMG to make necessary modifications. One of them was the Zijinshan Copper Mine, which was involved in the latest leakage.

ZMG said on its website that the Zijinshan Copper Mine had completed the required modifications by May 28, whereas the heavy metal leakage occurred in July.

Heavy metals have become the country's main source of pollution, with nearly 900 tons emitted every year, according to data from the Ministry of Environmental Protection.

Zhou Shengxian, who heads the ministry, said in April that the ministry had received 12 cases related to heavy metal pollution in 2009. These resulted in 4,035 people suffering from excessive levels of lead in their blood, while 182 had excessive levels of cadmium.

The ministry also said that one in four of China's 9,123 metal processing companies illegally emitted more heavy metal pollution than allowed.