The department said legal action could also be taken under licensing requirements of the lands and mines office, and regulations of the national water commission.

The department said the company had been ordered to report on its repairs to a breach in the silt pond embankment that contributed to the pollution, Bernama reported.

It must also continuously monitor all operational silt ponds to ensure no further pollution incidents occur.

The department said it will ensure that no additional pollutants or muddy water enter nearby river systems once the necessary repairs are completed.

Those involved in mining and industrial operations were reminded to implement effective pollution control measures, especially during the rainy season.

Yesterday, Johor executive councillor Fazli Salleh said the turbidity of raw water in the Johor river basin had risen dramatically to 37,400 units from a normal level of about 400 units.

He said the pollution was caused by soil movement that led to the collapse of a sand-dredging pond owned by a company at an inland sand mining site in Kota Tinggi.

Water supply to 455,499 consumer accounts has been disrupted, with half the number still affected this morning in Johor Bahru, Kulai and Kota Tinggi.

Water has been released from Linggiu Dam to aid dilution of the river water, and clean water is being delivered to affected areas via tankers.