A fugitive who allegedly murdered two officers in a small rural Australian town in the state of Victoria is being helped by some members of the community, police have said.

Dezi Freeman has been on the run since last Tuesday, when police arrived at his Porepunkah property to execute a search warrant, reportedly relating to a sex crimes investigation.

Mr Freeman, a known conspiracy theorist, escaped into thick bushland bordering the property, with a massive manhunt for him now in its seventh day.

His wife, Amalia Freeman, had earlier urged him to turn himself in and offered her condolences to the families of the officers he is alleged to have killed.

Victoria Police - which has previously appealed for Mr Freeman to surrender - says there has still been no sighting of the 56-year-old.

"People know the whereabouts of the person who has killed two cops," Superintendent Brett Kahan said in an update on Monday.

"You are committing an extremely serious crime by harbouring or assisting in the escape of Dezi Freeman."

He declined to specify how many people police suspected, or whether they were locals in the town of Porepunkah or nearby areas.

Police had arrested and promptly released Ms Freeman and a 15-year-old when raiding another Porepunkah property on Thursday night, but have not provided any additional information.

Ms Freeman said she and her children "respected the important work of Victoria Police and do not hold anti-authority views," in a statement released by her lawyers.

Heavily armed police, helicopters and armoured vehicles have now been searching the area where Dezi Freeman disappeared for almost a week.

The killings have revived questions over how Australian authorities deal with the threat of conspiracy theorists - three years after a hauntingly similar ambush of police in Queensland.

Mr Freeman had long espoused "sovereign citizen" views and had a well-documented hatred of authority.

Victoria Police say a thorough risk assessment was conducted before 10 officers had travelled to his property, but specialist police support had not been requested.