Water pollution caused by mine tailings leakage in Northeast China's Heilongjiang Province had reached 110 km downstream of the river by Tuesday afternoon, local authorities said Wednesday.

The leakage happened at 1:40 pm Saturday at the tailings pond of the Yichun Luming Mining Co., Ltd. in the city of Yichun. Although the leakage has been stopped after around-the-clock efforts Tuesday, part of the leakage polluted a local river, Hulan.

According to the monitoring by the provincial department of ecology and environment, the pollution was tested at Shuanghe Canal of Hulan River at 2 pm Tuesday, which is 110 km downstream of the incident site.

According to the pollutants found, the substance of molybdenum is 1.8 times higher than environmental requirements, that of COD is 4.7 times above the limit and petroleum is 0.4 times higher than the standard.

Hulan River is the major tributary of Songhua River, and feeds into Songhua in Harbin, the provincial capital.

The Ministry of Ecology and Environment sent a work team to Yichun on Sunday. About 1,200 people have been mobilized to stop the mine tailings leak.

Necessary measures, including setting up interception dams and placing flocculant and activated carbon, have been taken to reduce the water pollution.

Environmental monitoring along the river has been intensified. The cities of Tieli and Suihua have suspended water in-taking from the river and switched to alternate sources.