A man has been charged with theft, firearms and drugs offences after investigators combed a regional property for signs of Adrian Romeo, who has not been seen in five months.
Victoria Police believe the 43-year-old has met with foul play.
On Tuesday, investigators raided a property in Wildwood, on Melbourne's northwestern outskirts, with assistance from the Australian Federal Police's forensic search team, NSW Police cadaver dogs and the State Emergency Service.
Several dwellings and dams on the property were searched as part of the warrant.
The raid uncovered a gun, ammunition, drugs and four stolen vehicles, leading to the arrest and questioning of a 34-year-old man.
The Wildwood was charged on Tuesday night with firearms charges, possessing drugs of dependence and handling stolen goods in relation to the items found at the property.
There was no update on whether officers were able to locate a lead to Mr Romeo or if the Wildwood man was involved in his disappearance.
Mr Romeo, from Craigieburn, was last seen on February 10 when he told his parents he was going to Greenvale, a 15-minute drive from Wildwood, to visit friends.
He was driving his 2004 gold Toyota Camry, which police are yet to find.
Mr Romeo has not been seen or heard from since and his phone and bank cards have not been used.
Homicide squad boss Dean Thomas said police received anonymous information indicating there were people who knew Mr Romeo's movements "at the very end".
"I appeal to those people that have provided that information that they contact Crime Stoppers or their nearest police station so that we can pursue further investigations in relation to the information they have," Detective Inspector Thomas said.
Mr Romeo's disappearance has been deemed out of character.
He had little involvement with police and there was nothing to suggest he had links to organised crime.
Mr Romeo's cousin, Charlie, described him as a loving and caring person.
"He was loved by a lot of people. How this happened ... we don't know," he told reporters.
"The family is distraught. We are holding on to hope ... waiting for him to walk through the door."
The Wildwood man was remanded and will face Broadmeadows Magistrates Court on Wednesday.
