Police have charged a Victorian man over the murders of missing Wonnangatta campers Russell Hill and Carol Clay. 

Greg Lynn, 55, was on Thursday evening charged with two counts of murder after three days of questioning. 

Lynn — a Jetstar pilot with a love for camping — was arrested on Monday night at a remote campsite in Arbuckle Junction, 1.5 hours south of Wonnangatta in the state's east. 

The charges are the latest development in a captivating 18-month case, which first started on March 20 of last year when Hill and Clay were last heard from. 

The investigation ramped up a fortnight ago when police unveiled photos of a blue four-wheel-drive towing a trailer they believed could be linked to the case. 

Detectives were unable to eliminate the mid to late 1990s model Nissan Patrol and its trailer from their inquiries. 

Police on Tuesday were then seen towing away Lynn's 4WD to be taken for forensic examination in Melbourne. 
 Greg Lynn has been charged with two counts of murder. (Photo / Supplied via news.com.au) 

The car - although a sandy brown colour – closely resembled the dark blue Nissan Patrol police had been searching for in recent months following an appeal to the public for the owner of the car to come forward. 

Hill first left his Drouin home to embark on the fateful camping trip on March 19, before collecting Clay from her home in Pakenham in his white Toyota LandCruiser. 

The pair then travelled via Licola, spending one night at Howitt High Plains before heading into Wonnangatta Valley on March 20. 

Hill – who did not tell his wife he was with Clay – was last heard from the next day via HF radio, stating he was at Wonnangatta Valley in the Victorian Alps. 

The next day, campers found Hill's vehicle with signs of minor fire damage at their campsite, which was completely burnt out, near the Dry River Creek Track in the Wonnangatta Valley. 

Since that time, police have conducted extensive searches of the area, including missing persons squad detectives, local police, the search and rescue squad, air wing, dog squad and even the Australian Federal Police. 

Hill and Clay's bodies were yet to be recovered. 

Their family members have spoken out in the past few days, welcoming news a suspect had been arrested and desperate for answers about where their loved ones' remains were. 

Clay's sister Jill said her beloved 73-year-old sister's disappearance had been tough and hoped the man's arrest would bring closure. 

"Emotionally, it's brought up everything during that time – a lot of grief and pain. We haven't known how, we haven't know why, they just vanished," she said. 

"Now all of a sudden there's a glimmer and we might get some answers. 

"It would be such a relief to have those answers, to have a memorial for Carol and Russell." 

By - Anthony Piovesan and Rhiannon Tuffield, news.com.au