SEREMBAN (THE STAR/ASIA NEWS NETWORK) - Malaysian police said they have detained two suspects in Kelantan and seized an 18-wheeler truck believed to be involved in a waste-dumping incident that caused water-supply to be cut to parts of Selangor from Sunday (Oct 4).

The water supply disruption, which affected nearly 310,000 consumer accounts, was on Wednesday being progressively restored to the four districts in Selangor.

The waste was dumped near a river in Nilai, a Negeri Sembilan township which sits on the border with Selangor, forcing two Selangor water treatment plants to be shut down to avoid drawing in pollution.

The public is incensed with the water-supply cut, as it comes just a month after dumping of suspected chemical affluents in a Selangor river caused water supply disruption for nearly a week in the federal territories of Kuala Lumpur, Putrajaya and southern Selangor, which share water resources. Some 1.2 million consumer accounts were affected then.

Negeri Sembilan's state deputy police chief Che Zakaria Othman said the two suspects, who were the driver and attendant of the vehicle, were detained around 12.45pm on Tuesday.

"Based on public information, police managed to trace the vehicle back to Kelantan and detained the suspects," he told reporters. "We will apply for a seven-day remand order from the court later today to detain the duo."

He said based on preliminary findings, the suspects were employees of a transport company based in Kota Baru, Kelantan.

Senior Assistant Commissioner Che Zakaria said on Tuesday that based on preliminary findings, the waste was dumped along the banks of Sungai Batang Benar.

The dumping of the waste, believed to be liquid and semi-solid organic compounds, disrupted operations at Selangor's Sungai Semenyih and Bukit Tampoi water treatment plants on Sunday.

The supply is being restored in stages from Wednesday to Friday.