Several thousand litres of scheduled waste is believed to have been dumped into the Indah Water Konsortium (IWK) sewage system through a factory lot in Rawang, which caused the pollution in Sungai Selangor yesterday.

According to Gombak police chief Arifai Taware, authorities raided a factory lot in Taman Velox where they found 40 chemical tanks, each with the capacity of 1,000 litres...