A crime scene has been established in Victoria's alpine region with police focusing their efforts on finding the remains of Russell Hill and Carol Clay, after a man was charged over their murder.
The 55-year-old Caroline Springs man was on Thursday night charged with two counts of murder. He will face Sale Magistrates' Court on Friday morning.
Victoria Police Assistant Commissioner Bob Hill said investigators had discovered a crime scene within the Great Alpine Region on Thursday morning.
"We've located a specific area and we will be establishing a search parameter in the coming days and we are hopeful we will locate the remains of Mr Hill and Ms Clay," he told reporters in Melbourne on Thursday night.
"While this arrest is testament to months of dedication and tireless work by the missing persons squad detectives, this investigation is far from over.
"Forensic specialists will commence in searching at that location in the coming days.
"I hope that we will be able to locate the deceased and provide closure or closure to the families."
He expressed his condolences to the family, saying "the past 20 months has been an incredibly difficult time for them".
The man, has been in custody since a dramatic arrest on Monday night.
Specialist police swooped in to make the arrest at a remote campsite in Arbuckle Junction, 280km northeast of Melbourne.
Police seeking trailer potentially sold on Gumtree
His Nissan Patrol four-wheel-drive has been seized but police are yet to track down his trailer.
Earlier on Thursday, Victoria Police's top cop said detectives believed the silver-coloured trailer was sold online last year between March and July.
Chief Commissioner Shane Patton appealed for anyone who bought one at that time matching the description to come forward, in an interview on Melbourne radio station 3AW.
We are also continuing to appeal to anyone who knows the whereabouts of a blue coloured trailer that was attached to the Nissan Patrol to come forward," Assistant Comm Hill said on Thursday night.
"This trailer remains outstanding and police are keen to speak to anyone who purchased or received a similar trailer, particularly during the period of March and July last year. We believe the trial was sold on Gumtree."
Mr Hill and Ms Clay were last heard from on March 20, 2020 while camping in the Victorian Alps.
Mr Hill left his Drouin home on March 19 and picked up Ms Clay from her home in Pakenham in his white Toyota LandCruiser.
On March 20, Mr Hill - an experienced outdoorsman - made a call via high-frequency radio saying he was at Wonnangatta Valley.
Ms Clay, a former Victorian Country Women's Association president, told friends she was heading away and expected to return home on March 28 or 29.
Investigators were told the couple were camping together at Wonnangatta River near the Wonnangatta camping ground.
Campers found Mr Hill's car destroyed by fire at their campsite near Dry River Creek Track on March 21.
The pair have not been seen or heard from since.
Multiple searches have been conducted in and around the Wonnangatta Valley, including with cadaver dogs.
Earlier this month, police released images of a blue four-wheel-drive, believed to be a mid-to-late-1990s Nissan Patrol, taken by a safety camera in the area at the time Mr Hill and Ms Clay went missing.
Witnesses reported a number of sightings of the vehicle, including near the campsite, with police yet to track down the driver or exclude them as a person of interest.
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