PETALING JAYA - The Department of Irrigation and Drainage (DID) is helping the police drain water from a stream near the Idaman Apartment in Damansara Damai, here, where the body of Zayn Rayyan Abdul Matiin was found.
It is understood that works were being carried out as an effort to search for new evidence related to the murder of the victim.
Earlier, personnel from the Police Forensic Unit arrived at 11.45am.
Several members from the DID also arrived before the operation to pump water from the stream began.
Media practitioners who were at the location, however, were not allowed to go near the area.
On Monday, Selangor police chief Datuk Hussein Omar Khan said the police suspected that only one individual was involved in the murder of the autistic boy.
Hussein said this was based on clues, signs of struggle and injuries found on the victim's body.
He said the police were also examining video recordings from dashcams obtained from several vehicle owners who were residents of the Idaman Apartment to assist in the investigation.
Zayn, 6, was reported missing last Tuesday afternoon and was found dead in a stream located 200 metres away from his residence the next day.