Vietnamese environmental police on Thursday caught the state-owned Sonadezi Corporation red-handed discharging untreated waste into the Dong Nai River in the southern province of the same name.
After finding smelly sewage flowing from the sluice gates of the company's waste treatment facility into the river, they raided the plant and discovered that the waste treatment system did not work, and untreated waste was being dumped directly through three underground pipelines into a ditch that ran into the the river.
Tran Quang Thoa, the company's deputy general director, and three operators of its waste treatment plant, admitted to the act.
The plant has signed contracts to treat sewage for 42 companies in the Long Thanh Industrial Zone, Senior Lieutenant-Colonel Cu Nam Tien of the Environment Police Department told Thanh Nien.
It is estimated that the plant has discharged around 14 million cubic meters of sewage into the Dong Nai River over the last five years, he added.
Sewage samples have been taken for testing, police said.
Sonadezi Corporation is the main investor in industrial zones in Dong Nai Province.