Johor police chief Ayob Khan Mydin Pitchay, however, said the matter was still being investigated, in collaboration with the Johor environment department (DoE).

“We are still assisting and cooperating with the DoE, and there may be follow-up operations. We believe the lorry was ferrying this chemical waste from another location.”

According to him, the interrogation of nine suspects, including the owner of the premises, was still ongoing.

“Thus far, (investigations) only involved the premises that we raided that day. That is why we need to conduct a follow-up operation. We will find out how these waste materials were brought there for disposal,” he told a press conference at the Johor contingent police headquarters today.

Meanwhile, Johor DoE director Mohd Famey Yusoff was reported as saying that another suspect who was arrested yesterday had been released on police bail, while the case was being investigated under Section 34B of the Environmental Quality Act 1974.

In the incident which occurred at 10pm on Tuesday, four women were rushed to hospital due to shortness of breath, while 102 residents from 25 families in Kampung Baru Sri Aman were evacuated following the discharge of foul smell, believed to have been caused by scheduled waste dumped into the river.