South Australian police are appealing for any dashcam footage that may help their investigation into the suspected murder of mother-of-two Tanja Ebert.
They said the last independent sighting of the 23-year-old woman was about 3:20pm on August 8, when she visited the South Australian Museum in the Adelaide CBD with her family.
A search of the family's vast sheep station at Mannahill, north-east of Adelaide, started last Wednesday but had now been scaled back, police said.
The young woman's 41-year-old husband, Michael Burdon, shot himself dead at the property after police arrived there on Wednesday in their investigation of Ms Ebert's disappearance.
Police searched the house and outbuildings as part of their check of the 410-square-kilometre pastoral property.
Detective Superintendent Des Bray said the search was extensive but did not locate anything of note.
"There was very significant excavation done adjacent to a creek near the homestead, where recent earthworks had been undertaken, but sadly that didn't reveal anything," he said.
"It has been an extensive search. It's very frustrating, and we are working hard to get a result for Tanja's parents."
Commissioner's inquiry into man's death
Police said they had gained no information about the missing woman's location from her husband before he took his life.
The precise circumstances of Mr Burdon's death are under investigation, with police launching a commissioner's inquiry.
Police also searched in the Roseworthy area, north of Adelaide, after being told Ms Ebert got out of the family car when it pulled up there on August 8.
Major Crime detectives who are trying to piece together Ms Ebert's last movements have urged that anyone who travelled between Roseworthy and Mannahill, in either direction, between 7:00pm and midnight on August 8 contact them if they have any dashcam footage of the route.
"It's actually quite rare for people to commit a murder and not to tell somebody," Superintendent Bray said.
"We encourage anyone with information to contact police.
"They should think about Tanja's parents and children and come forward."
