South Australian police have upgraded the disappearance of four-year-old Gus Lamont to a major crime investigation and have officially identified a suspect. The person of interest is a former resident of the Oak Park sheep station where Gus lived. While this individual has stopped cooperating with the authorities, police confirmed that Gus's parents are not suspects.

Investigators have ruled out the possibility that the boy walked away on his own or was kidnapped by a stranger. Detective Superintendent Darren Fielke stated that officers identified the suspect after finding contradictions in the information provided by family members. The massive search effort near the town of Yunta has included mounted police on horseback, divers, drones, and expert trackers covering a vast area of the outback.