An arrest has been made over the disappearance of missing Victorian campers Russell Hill and Carol Clay.
The pair, who were in a secret relationship, vanished in March 2020 after embarking on a camping trip in the Wonnangatta Valley in the Victorian Alps.
Victoria Police said a 55-year-old Caroline Springs man was arrested about 5.30pm yesterday and will be interviewed by police this morning.
They said the investigation remains ongoing and encouraged people to come forward with information.
No charges have been laid.
Mr Hill's car was found on March 21 last year at a campsite near Dry River Creek track which was destroyed by fire.
Mr Hill, 74, was last heard from on March 20 when he made a call via HF radio saying he was at Wonnangatta Valley.
Ms Clay, 73, told friends she was heading away and expected to return home on March 28 or 29.
Earlier this month, police released images of a blue four-wheel-drive - believed to be a mid-to-late-1990s model Nissan Patrol - taken by a safety camera in the area at the time Mr Hill and Ms Clay went missing.
Police believe the pair may have had an altercation with another camper at the campsite, possibly the driver of the blue 4WD.
Carol Clay's sister Jill told Channel Nine's 60 Minutes earlier this month the pair has been on several camping trips together.
She said Mr Hill's wife Robyn or his daughters were unaware of the affair.
Victoria Police said it did not intend to provide further information over the development at this stage.
Anyone with information is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential crime report online.
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