PETALING JAYA: Autistic child Zayn Rayyan Abdul Matiin, who was found dead in a stream in Damansara Damai, near here, yesterday, is believed to have been murdered elsewhere before his body was dumped there.

Bukit Aman Criminal Investigation Department director Datuk Seri Mohd Shuhaily Mohd Zain said the post-mortem results showed that the six-year-old boy had died in a 48-hour period before his body was found.

"Based on the autopsy findings, we have concluded that the victim did not die at the scene. Maybe at another place before his body was placed there (stream). For sure, he did not die of drowning " he told a press conference at the Petaling Jaya district police headquarters here last night.

Mohd Shuhaily said the post-mortem showed that apart from injuries to the neck and body, the victim also suffered injuries while trying to defend himself.

He said preliminary investigations showed that the stream path was not a usual route for the local community and police did not rule out the possibility that the suspect was familiar with the location.

He said police would look for evidence at the location of the incident to help trace the suspect, and did not rule out the possibility that the individual or individuals involved were from the area.

Police had already recorded statements from the boy's parents, he said.

"Police and the local community (involved in the search) passed the place for two days but did not find the victim, whose body was found late on the second night.

"We view this case seriously and ask anyone with information to come forward and help in the investigation," he said.

Mohd Shuhaily said investigations so far showed that Zayn Rayyan's death was consistent with a murder case.

Zayn Rayyan was reported missing on Tuesday afternoon in Damansara Damai and his body was found in the stream at about 10 pm Wednesday night, about 200 metres from his house in Apartmen Idaman.

His body was found by a search party comprising local residents.

Zayn Rayyan's mother realised that he had gone missing while climbing up the stairs to their house on the third floor at about 12.30 pm, with the boy last seen entering a bushy area near Apartmen Idaman.

-- BERNAMA