Police have sought assistance from Interpol in their investigation into the murder of Zayn Rayyan Abdul Matiin as investigators struggle to find more credible leads to crack the case.

According to Selangor police chief Hussein Omar Khan, they have asked the international police to run a database check on at least one DNA profile discovered during the probe.

"We have sought assistance from Interpol to check with their database because we have several leads which, despite being non-conclusive, we believe this information can help with our investigation," he said.

Hussein was speaking at a press conference held at Gombak police headquarters earlier today when he was asked to update on the murder case.

He confirmed with Malaysiakini later that the information that police were checking with Interpol was related to DNA that police discovered during the investigation.

Selangor police chief Hussein Omar Khan

Based on media reports, authorities discovered some evidence in the form of DNA samples and fingerprints during a post-mortem procedure on Zayn Rayyan's body earlier this month.

However, it remains unclear how many sets of DNA and fingerprints were found then.

During the press conference today, Hussein said police are facing an uphill task in their efforts to solve the case.

So far, he said, the information that has been gathered by investigators could provide "minimal" help.

Primary crime scene not found yet

This includes the fact that the primary crime scene was yet to be found.

"... the location where we found the victim was a secondary crime scene. Basically, police could not get much physical evidence from the secondary crime scene.

"So, in this case, it is a challenging task for the police to find evidence that can lead us to arrest the perpetrator or suspect," he said.

This was despite police having carried out massive operations to find more leads that could facilitate the investigation, including house-to-house searches, mass DNA screenings and reviewing footage from CCTVs around the area.

So far, according to the police chief, investigators have collected a total of 248 DNA samples and recorded 225 statements from individuals.

"From the samples we have sent to the Chemistry Department, there have been no positive outcomes that can help us with the investigation at this juncture."

However, Hussein stressed that police will not stop looking for more evidence and vowed to continue their investigation until the perpetrator is brought to justice.

"We will not lose hope. We believe we will find the perpetrator. Maybe not today, but we will continue our efforts until we find the person responsible," Hussen said.

Zayn Rayyan, a six-year-old autistic child, reportedly went missing in the afternoon of Dec 5.

According to news reports, the boy and his mother were taking the stairs to their apartment unit at Level 3 when she realised that he was nowhere to be seen.

The mother then tried searching for Zayn Rayyan, before she posted on Facebook seeking assistance from anyone around the area to locate the boy.

A search party was later mounted by the authorities and assisted by local residents to look for the boy.

After efforts to locate the victim were unsuccessful, police launched a door-to-door search operation in the evening of Dec 6, before Zayn Rayyan's body was discovered by a stream about 200m from his home about 10pm.

He was initially presumed to have drowned, but police later reclassified the case as murder after a post-mortem carried out by forensics experts revealed that the victim had been strangled.

There were also defensive wounds found on his body, according to police.