Last week, Detectives from Task Force Southern travelled to the Mid North region to continue their search in relation to the ongoing investigation.
Police confirmed that human remains have been located in an underground cement water tank on an abandoned property southeast of Orroroo.
Detectives believe these remains are of long-term missing person Robert Atkins.
So far there have been five people charged in connection with the disappearance of Robert Atkins, including one who has been charged with murder.
Detective Superintendent Bray said Mr Atkins was last seen alive at Port Pirie on November 16, 2020.
Anyone with further information is urged to contact Crime Stoppers.
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