SPAN chairman Charles Santiago told FMT that this was uncovered after a site visit to a factory linked to the incident, as part of a three-day inquiry by the commission.

He added that SPAN is trying to bring together all relevant parties and government agencies to get a sense of what transpired in the incident.

“This is to ensure it does not occur again. Plus, today’s visit was quite telling, revealing that local laws and regulations were not followed.”

However, he declined to disclose further details, saying the commission would release a full report on the pollution incident next week.

On July 23, four water treatment plants were temporarily shut down after odour pollution was detected at Sungai Kundang and Sungai Sembah.

Various regions of Kuala Lumpur, Petaling, Klang, Shah Alam, Gombak, Hulu Selangor and Kuala Selangor experienced unscheduled water disruptions as a result.

Odour pollution has led to repeated water cuts in Selangor, with multiple incidents typically occurring within a year.