A Beijing-based kitchen garbage processing company was caught decomposing of waste illegally with sulfuric acid and discharging the strong acidic solution into the city's Yongding River, Legal Evening News said on Monday.

Located in Yongding county of the city's Mentougou district, Beijing Aoliyi Economy & Trade Co., Ltd. is a legitimate enterprise with a majority of its business in kitchen garbage processing.

Instead of applying a regulated and clean manner to process waste with an oil-water separation machine, the company has been exposed of processing kitchen waste with heated sulfuric acid.

Legal Evening News launched a secret investigation after a resident surnamed Hong, who lives in a community near the company, contacted the newspaper.

Hong said he and other local residents have been suffering from irritant gas released from the plant that burns the residue of waste with sulfuric acid.

Pollutants discharged by the company have contributed to the deaths of trees along the banks of Yongding River, according to Hong.

The investigation found that a solution of decomposed waste was taken out and discharged secretly in sewer lines by a tank truck dispatched from the plant on several nights. A sample of the solution was tested as highly acidic material.

After the case was reported to the municipal environment protection department, a campaign jointly launched by the green agency and security department was carried out between April 8 and 12.

A tank truck with six tons of strong acidic solution on board was seized in a police raid last Saturday.

At the plant, a drainage ditch hidden under iron plates was found. The pipeline linking Yongding River was built to release pollutants directly into the river.

National regulations say illegal discharging and dumping of dangerous materials weighting over three tons can constitute a crime of polluting the environment.

Operations at the company have been suspended, and further investigation is still underway.