In a Bernama report, Selangor police chief Hussein Omar Khan said the sock would be sent to a laboratory for analysis to ascertain whether it belonged to Zayn – who is believed to have been murdered.

“We only found one piece, but we need to confirm whether it belongs to the child or not,” he said.

The fire and rescue department and the irrigation and drainage department yesterday assisted the police in draining the water at the stream to look for evidence.

Zayn, a six-year-old autistic boy, was reported missing on Dec 5.

His body was found the following day in a stream about 200m from the block where he lived at Apartment Idaman in Damansara Damai here.

Police previously said they believed Zayn was murdered based on the strangulation marks and signs of struggle found on his body.