South Australian police have found a 21-year-old woman’s body in a shallow grave in the Flinders Ranges, with her 20-year-old boyfriend arrested for failing to report a death to the coroner.

A 21-year-old woman was last seen at Plympton North nursing home Southern Cross Homes on Friday and reported missing at a city police station on Saturday.

Police said Major Crime detectives interviewed the 20-year-old man and escorted him to a site at Moralana Creek, about 40 kilometres north of Hawker, where officers found the shallow grave.

Forensic experts and a pathologist attended the scene and helped to locate the woman’s body.

Police announced the woman’s body had been found late on Monday afternoon.

The man was arrested for failing to report the death to the coroner and remains in police custody.

He is expected to face the Port Augusta Magistrates Court tomorrow.

Police are continuing their investigations.

More to come.