Gus Lamont: Everything we know as police announce suspect and rule out two theories about 4yo’s disappearance

After months of searching, police revealed a major update in the investigation into the disappearance of missing four-year-old Gus Lamont on Thursday.

From the new suspect who lived with the missing boy, to all of the police’s theories — here is everything we know about what has now been declared a “major crime”.

What happened the day Gus went missing?

Little Gus was last seen by his grandmother playing on a mound of dirt at Oak Park Station, 43km south of Yunta, at about 5pm on September 27, 2025.

He lived at the rural South Australia property with family members, including his younger brother.

Police were told that at 5.30pm when his grandmother tried to call him inside, the boy had vanished.

The four-year-old was reported missing later that same day. Speaking to press on Thursday, detective superintendent Darren Fielke said it was possible Gus could have been at the property when police later arrived to search it.

“Police were on scene quite quickly … when they were advised Gus was missing. There was time in between but yes, it is possible,” he said.

It is unclear how long it was after 5.30pm that police were called to the property.

Gus was last seen wearing a blue T-shirt with a yellow minion graphic on the front. He wore a grey sunhat, and light-grey long pants with boots.

What are the police theories?

Police had three main theories about little Gus’ disappearance — two of which they confirmed had since been ruled out.

The first theory relied on Gus still being alive, which police confirmed on Thursday has been eliminated.

Det-Supt. Fielke confirmed that investigators “don’t believe, now, that Gus is alive”.

“This is one of three investigation options that have been explored by the members attached to Taskforce Horizon,” he said.

“The other two investigation options are focused on Gus being abducted (by an unknown person) from Oak Park Station, or whether someone known to him was involved in his disappearance and suspected death.”

In the weeks following his disappearance, a 94 sq km radius around the Oak Park Station property was scoured by all available emergency services, SES, the ADF, and an army of volunteers in addition to aerial searches conducted by drones and helicopters.

Det-Supt. Fielke said the efforts provided little evidence to suggest Gus had wandered from the home. After searching three dams, a water course and six mine shafts, police are confident the boy did not fall or drown.

Further, Det-Supt. Fielke said the opportunity for anyone to abduct Gus was “extremely low” given the number of gates on the property that are regularly locked and secured by station owners and property owners in the area.

No vehicles foreign to the area were identified by the property owners or neighbours when Gus went missing.

Det-Supt. Fielke explained that if a vehicle was in the area, dust would have been seen in the air.

“There was no dust, no sighting of any vehicle at the time Gus went missing. There’s been no foreign tracks located arriving or leaving the property,” he said.

“We have found no evidence to suggest that Gus was abducted from the property.”

Who is the suspect?

Having ruled out the theories that Gus had wandered or been abducted, police are pursing a line of enquiry into their third theory — that someone known to the boy was involved in his disappearance and suspected death.

On Thursday, it was announced that a suspect had been identified, and that they had lived with Gus before he disappeared.

It was also confirmed that the suspect was neither of the missing boy’s parents.

“A person who resides at Oak Park Station has withdrawn their support for police and is no longer cooperating with us,” Det-Supt. Fielke revealed.

Task Force Horizon, a team assembled to head the investigation into Gus’ disappearance, executed a search warrant on the Oak Park Station on January 14 and 15.

“Further comprehensive forensic search was conducted of the Oak Park Station homestead. A number of items were seized, including a vehicle, a motorcycle, and some electronic devices,” Det-Supt. Fielke said.

“All of these items are now subject to forensic testing. The person who has withdrawn their co-operation is now considered a suspect in the disappearance of Gus.”

The search involved AI software

The search for Gus Lamont is the largest and most intensive every carried out by South Australia police with regard to a missing person.

It involved 163 state police officers and 230 personnel from other services including the SES, the ADF, First Nations trackers, and community volunteers.

“The resources were deployed at Oak Park Station for over 20 days and there were eight separate ground searches that extended to a radius of 5.47km (95 sq/km) from the Oak Park Station homestead. The search area included three dams that were searched on two occasions – this has included draining the dams,” a police statement said.

“Police have also searched six mine shafts located within a 10km radius of the Oak Park Station homestead.”

The search effort also involved aerial searching, including infrared imaging in a 12km radius of the property. Specialised camera equipment also captured images over an area of 706 sq km.

“This imagery has been processed using specifically designed, specialised AI software programs and reviewed by Task Force Horizon investigators,” police said.

Another search was conducted on February 2 for the remains of Gus, but nothing was found.

What happens now?

The investigation is still ongoing and no charges have been laid.

“I anticipate there will be further searches at Oak Park Station and at several sites on an adjacent national park to locate Gus as new information and intelligence comes to hand as the investigation continues,’’ Det Supt. Fielke said.

“The disappearance of any child is tragic and distressing not just for Gus’ parents, but also the entire community sharing their grief.

“I can reassure the community that despite the complex and challenging nature of the investigation, Task Force Horizon will continue to thoroughly and meticulously investigate the disappearance of Gus until we get a resolution.

“We are all focused and determined to locate Gus and return him to his parents.’’

Anyone with information that might assist the investigation is urged to contact Crime Stoppers on 1800 333 000.