Alleged cop killer Dezi Freeman has the ability to evade police for weeks or even months, a leading criminologist has warned, as the hunt for the so-called sovereign citizen enters its fifth day.

Previously known as Desmond Filby, the 56-year-old remains on the run after he allegedly murdered two police officers and wounded another at his Porepunkah property in Victoria’s High Country on Tuesday. 

Dr Vincent Hurley, who was a NSW police officer and negotiator for 30 years, predicted Freeman could hide for a while as he is familiar with the area, but the weather could give police an advantage.

‘My gut feeling is that he won’t come out of his own free will because he’s already allegedly murdered two people,’ he told Weekend Today on Saturday. 

‘And being that right-wing extremist, I don’t think it’s going to end well.’

Asked whether Freeman has the capability to evade police for weeks or even months, Dr Hurley said: ‘Absolutely because it’s his backyard. 

‘The thing that’s going against him will be the weather and whether he’s got anything out there, like ammunition stashed away, or food or extra clothing.

‘The weather conditions will wear him down, physically as well as psychologically, because he’ll be out there having no rest.’

Tough conditions have impacted search efforts as rain and hail batter the rural town along with blizzard-like conditions on Saturday. 

Dr Hurley suggested Freeman would ‘always be on edge’ believing that officers are watching him, adding ‘so the police have got the advantage at this point in time’.

‘He could well have a bunker or something stashed out there,’ he said.

‘(But) I would tend to think that, whilst it’s a possibility, possibly not because it would appear it was a bit of a spur of the moment thing. 

‘That makes me think, as a former negotiator, that he doesn’t have anything out there. There’s a possibility but I tend to think not.’

There have been no confirmed sightings of Freeman since he fled into bushland near Porepunkah, about 300km northeast of Melbourne, on Tuesday morning.

Formerly Dezi Filby, he is accused of killing Detective Leading Senior Constable Neal Thompson, 59, and Senior Constable Vadim De Waart, 35.

It’s been revealed that 10 officers attended Freeman’s property on Tuesday to execute a search warrant and to speak with him about alleged sexual offences against a child under the age of 16.

Heavily-armed officers searched several properties and nearby bushland in the area on Thursday as the manhunt ramped up.

Police then issued a direct message to the fugitive gunman, with Superintendent Brett Kahan saying: ‘Ring 000 and we will provide a surrender plan.’

Dr Hurley said the video message was a strong strategy as it ensures Freeman knows there are options available to him and that ‘he’s not boxed in by police’.

‘That will play on his mind. It will give him an ‘out’, an open door so he can come out of his own free will, if he wishes,’ the criminologist said.

‘The police don’t want to close the door and say “this is what’s going to happen” without giving him options… whether he surrenders or not is entirely up to him.’

On Thursday night, Freeman’s wife Mali and 16-year-old son were arrested at a home in Porepunkah. They were questioned by police before being released.

‘There may or may not be charges that follow,’ Chief Commissioner Mike Bush said. 

By speaking to the family, police would not only be trying to understand the psychology of Freeman but also gathering intelligence, Dr Hurley said.

‘For example, (they might ask about) the firearm capacity that he might have, his state of mind, what actually triggered this event,’ he said.

‘That information will be passed on to the negotiators to get an understanding because, being a sovereign citizen, he’s (a) right-wing extremist.

‘That group of individuals are very much anti-police so they’ll be trying to work out his frame of mind.’

Porepunkah residents have been urged to remain vigilant and avoid unnecessary travel as the manhunt continues.