Chai Kin Sang, 62, and his son, Wern Teik, 31, pleaded not guilty to both charges which were read out before judge Maziah Joary Mohd Tajudin.

On the first count, the duo were alleged to have committed mischief by causing waste products containing hazardous materials from the premises of FG Autoparts Sdn Bhd to be disposed into a waterway that flows into Sungai Gong despite knowing it would cause water shortage.

They were charged with committing the offence at the company premises in Batu Arang, Rawang, between Oct 17 and Oct 19.

The charge, framed under Section 430 of the Penal Code, provides for imprisonment of up to 30 years, or fine, or both, if found guilty.

On the second count, they were jointly charged with releasing waste containing hazardous material from a similar workshop into a waterway that would flow into the same river at the same place and time.

It was framed under Section 25 (1) of the Environmental Quality Act 1974 which provides for a maximum fine of RM100,000 or imprisonment for up to five years or both, upon conviction.

The court allowed both the accused to be released on bail of RM400,000 with one surety and to report themselves at the nearest police station once a month.

They were also ordered to surrender their passports to the court and not to intimidate witnesses in the case.

The court has set Dec 16 for mention and submission of documents.

Deputy public prosecutor Muhamad Iskandar Ahmad prosecuted while both the accused were represented by lawyer Muhammad Nor Izzat Nordin.