The man arrested over the suspicious disappearance of Victorian campers Russell Hill and Carol Clay may have sold his trailer, with police urging the new owner to come forward.

A 55-year-old Caroline Springs man, who has been held in custody since Monday, is being questioned about the campers, who vanished 20 months ago in the state’s high country.

He was arrested on Monday night by specialist police at a remote campsite in Arbuckle Junction, 280km northeast of Melbourne.

His Nissan Patrol four-wheel-drive has been seized but police are yet to track down the man’s trailer.

Detectives believe the silver-coloured trailer was sold last year between March and July and have issued an appeal to anyone who bought one at that time matching the description to come forward, Chief Commissioner Shane Patton said.

“If they’ve received one or purchased one and … they don’t absolutely know who they purchased it from or how they came into possession of it — there might be something suss about it — if they could contact Crime Stoppers that would be fantastic,” he told Melbourne radio 3AW on Thursday.

Mr Patton confirmed the man, a stood-down check captain with budget airline Jetstar, was spoken to by police previously before his dramatic arrest.

The Victoria Police boss stressed there was “no urgency” to lay charges against him, noting a person can be held in custody for “a reasonable time” with no set limit under the Crimes Act.

“We’re not rushing into anything here,” he said.

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.

Police believe the pair may have had an altercation with another camper, possibly the driver of the blue 4WD.

It was towing a trailer and was heard performing a 20- to 30-point turn on a narrow track the night the pair vanished.