Industrial pollution is behind the deaths of tens of thousands of birds on the pasture of Uxinzo town of north China's Inner Mongolia Autonomous Region, the Beijing Times reported.

An industrial park was built in the town ten years ago that discharges sewage directly into the Tsagaan Nuur Lake, through a huge pipe buried underground, according to local herdsmen.

To ensure that nobody would get close, the park owners sent people to stand in the two roads leading to the sewage outlet during the daytime.

However, when there were no guards at night, many herdsmen saw sewage water run into the lake. According to the herdsmen, the smell from the water was overpowering.

In July, tens of thousands of birds were found dead in the area, many of which were rare birds under the national level protection. Some herders said that government authorities had sent people to collect and bury the dead birds at intervals.

Herdsman Bulgoude said that the environment has been deteriorating over the years. Many wild birds and plants have died, and the underground water level has drawn down. Local residents have to dig wells as deep as 200 meters to hold water.

Heavy pollution in Uxinzo town is not a single case in the vast Inner Mongolia. Days ago, the Beijing Times reported a sewage lake in Tengri desert. Factories discharged untreated sewage into the desert, and a sewage lake formed. The over-exploitation of underground water also damaged the ecosystem of the surrounding area.

Mu Guangfeng, from the environmental protection ministry, who is in charge of environmental evaluation, said the water under the deserts is formed over hundreds of millions of years. Once the water gets polluted, there is no way to restore it.