Police have returned to Oak Park Station in South Australia to search for new evidence after naming a suspect in four-year-old Gus Lamont’s disappearance. Gus went missing on 27 September 2025 from the family's remote sheep station, triggering one of South Australia's largest searches. He was last seen playing outside at 5 pm, but was gone when his grandmother called him inside half an hour later. Initial police belief was that Gus had wandered off based on information from residents at Oak Park Station. The 60,000-hectare property, about 300 km inland from Adelaide, saw drones, dogs, divers, volunteers, and defence personnel join in searching the area. Survival experts advised the chances of finding Gus alive were low, so the search shifted to recovery. Police had not found evidence of foul play but did not rule it out. The family was cooperating consistently. On 5 February, police declared the case a major crime. Detective Superintendent Darren Fielke said police found "a number of inconsistencies and discrepancies" in the family's information. A person living at Oak Park Station who no longer cooperates with police is now a suspect. Police had considered three theories: Gus wandered off, he was abducted, or someone known to him was involved. They ruled out the first two, choosing the third theory. Fielke confirmed the suspect is not one of Gus’s parents. Gus’s two grandmothers, through lawyers, said they are “devastated” by the case now being a major crime and that the family “cooperated fully” and want Gus to be found and reunited with his parents. Task Force Horizon detectives returned to Oak Park Station for at least two days to continue their search. South Australia Police (SAPOL) said, “An update on the search activities will be provided as they progress.” Anyone with information is urged to contact Crime Stoppers on 1800 333 000.