A man and a woman from South Australia's Mid North have been charged with the theft of an excavator that police say is linked to the murder of an Adelaide man.
The 60-year-old man and 57-year-old woman were arrested on Saturday morning at a property in Booborowie, near where police found 140 bullets on Friday.
The search in and along the Hutt River and next to the Goyder Highway between Booborowie and Spalding was in connection with the suspected murder of 31-year-old Adelaide man Robert Atkins in 2020.
It was sparked by a tip-off that a middle-aged man and a woman were seen acting suspiciously in the area last month.
The excavator that the arrested couple is accused of stealing was found in the remote Northern Territory town of Borroloola on Tuesday.
Police say the vehicle, worth $50,000, was stolen from Meadows, in the Adelaide Hills, in November 2019.
On Friday, police said the excavator was "linked to suspects in the investigation" of Mr Atkins's suspected murder.
The man and woman were bailed to appear in the Clare Magistrates Court in September.
Taskforce looking into three deaths
The investigation into Mr Atkins's suspected murder is part of Taskforce Southern, an operation looking at suspicious deaths associated with the methamphetamine scene in southern Adelaide.
Police believe Mr Atkins, of Christie Downs, was murdered in November 2020 over a $1,000 drug debt.
He was reported missing in January 2021.
A search for his body and any evidence related to his death in an area farther north in February this year turned up nothing.
Taskforce Southern is also looking into the murders of Trevor King and Jeff Mundy.
Mr Mundy was last seen in late 2020.
Mr King was found dead at West Lakes in January 2020, in what detectives now believe was a staged drug overdose.
Rewards worth $200,000 are on offer for information connected with each of the three deaths.
