Four water treatment plants that had their operations suspended after another case of river pollution was detected in Selangor will resume operations and water supply is expected to be restored within 24 hours, according to Environment and Water Minister Tuan Ibrahim Tuan Man.

Tuan Ibrahim said initial investigations revealed a similar scent to the previous Sept 3 pollution incident that affected 1.2 million households.

He said the ministry did not rule out the dumping of solvent by illegal factories operating around Selangor.