Police are expected to return to the area to conduct further inquiries on Tuesday as the investigation continues.
The renewed search effort is expected to be completed in the next two days, police said.
“Members attached to Task Force Horizon … have returned to Oak Park Station to continue searching for evidence,” a statement read.
“It is anticipated that Task Force Horizon detectives will remain in the area for at least the next two days.”
The boy’s disappearance is now being investigated as a major crime, with police revealing earlier this month they had identified a suspect who they believe was known to the little boy.
No arrests have been made or charges laid in relation to the missing boy.
Detectives said they no longer expect to find Gus alive when they revealed bombshell details of their ongoing investigation earlier this month.
Detective Superintendent Darren Fielke said there had been “discrepancies” and “inconsistencies” in the information provided by some of Gus’ family members.
“As a result of these inconsistencies, and investigations into them, a person who resides at Oak Park Station has withdrawn their support for the police and is no longer co-operating with us,” he said.
Superintendent Fielke said the suspect was not one of Gus’ parents.
“The person who has withdrawn their co-operation is now considered a suspect in the disappearance of Gus,” he said.
“I do want to stress, however, that Gus’s parents are not suspects in his disappearance.
“I can’t give you any more information about the suspect or where the suspect is and why that person is a suspect.
“When we have a suspect in an investigation, it can … have its own challenges, so we’re working through those.”
The little boy’s grandparents hired separate lawyers after the new details were revealed.
Gus’ grandparent Josie Murray has hired criminal lawyer Andrew Ey, and his grandmother Shannon Murray is being represented by defence lawyer Casey Isaacs.
The legal team confirmed they were representing Gus’ grandparents in a statement released on February 6.
“Andrew Ey and Casey Isaacs can confirm that we act for Josie Murray and Shannon Murray respectively,” the lawyers said.
They issued a statement on behalf of the boy’s grandparents: “We are absolutely devastated by the media release of Sapol Major Crime.”
“The family has co-operated fully with the investigation and want nothing more than to find Gus and reunite him with his mum and dad.”
It is not unusual for potential witnesses to seek legal advice.
There is no suggestion that Josie or Shannon Murray were involved in Gus’ disappearance.
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