Detective Senior Constable Stuart Sims, of the Colac police crime investigation unit, said the bodies of the man aged in his 20s and a woman, also aged in her 20s, had yet to be formally identified but they were believed to be from Melbourne.

He said the bodies were discovered by a jogger about 11am on Saturday on a dirt track off Birregurra-Forrest Road, about three kilometres from Forrest.

Detective Senior Constable Sims said autopsies had now been conducted.

The woman, who was found in the boot of a vehicle, had suffered injuries consistent with being assaulted.

Investigations into the man's cause of death are continuing but his death is being treated as not suspicious.

The families of the deceased are still in the process of being notified.

A report is being prepared for the coroner by Colac detectives with the assistance of the Victoria Police homicide squad detectives.

Anyone with information about the deaths can contact Crime Stoppers on 1800 333 000.

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