Lead investigator Detective Inspector Gary Jubelin will be in Port Macquarie this week to continue the new line of inquiry which is linked to an alleged paedophile ring. 

The revelation of a new line of inquiry came hours after the release an emotional video on Friday of William's parents asking for him to be returned to a public place.

Det Insp Jubelin on Sunday echoed Detective Superintendent Michael Willing’s praise for William’s parents bravery.

“It has been very difficult for the parents to process this (latest lead),” Det Insp Jubelin said.

“As you could imagine, it takes them to a very dark place.”

“(While) we have grave concerns, until we can say with certainty that William is deceased we will treat it as if he is still alive.”

The revelation of the possible involvement of a paedophile ring should not create an “environment of fear” in the community, the officer said.

“In this day and age I have an expectation that everyone would be wary with regards to (an investigation regarding) children,” he said.

The investigation is now “fast-paced” and police are “throwing everything we have got into finding out what happened to William”.

“Without compromising our investigations, the information we have received we consider (it) significant and are fully exploring all aspects of the information,” Det Insp Jubelin said.

“We have been receiving a lot of information since the heartfelt plea from family, but we are not relying solely on information from public.”

 William's parents, who can't be named or identified for legal reasons, on Friday asked for any one with information on their son to come forward. 

“Just give him back...give him back," his mother pleaded.

 “Take him to a church, take him to a police station, take him to a school.

“Give him to someone...give him back,” she begged.

“You can’t take children, you just can’t take children...he’s three! He’s three years old, he’s only lived for three years, it’s ridiculous. 

"We need to know where he is and we need to know what happened to him .... 'cause we can't live forever... like this. His sister can't grow up never knowing what happened to her brother."

Further searches have taken place recently, Det Supt Willing said on Friday.

But he refused to be drawn on whether police had located specific items of William's including the Spiderman suit he was wearing on September 12 last year. 

“If anyone has any knowledge of persons they suspect may be involved, please come forward to police,” Det Insp Jubelin said on Sunday.

Anyone with information about William’s disappearance is urged to come forward via Crime Stoppers. Police are urging anyone with information in relation to this incident to call Crime Stoppers on 1800 333 000 or use the Crime Stoppers online reporting page.

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