A major hunt is continuing in the Australian state of Victoria for a man accused of shooting dead two police officers on his semi-rural property, and injuring a third.

Police have confirmed that they are searching for Dezi Bird Freeman, a conspiracy theorist and self-described sovereign citizen who rejects government and law.

Freeman, 56, has a long history with the police, and his hatred of authority has been well documented in online posts, videos, and court documents.

He has called police terrorist thugs, compared them to Nazis, and tried to arrest a magistrate during court proceedings.

Less than a week before the shooting of two police in Porepunkah, his wife, Mali, had told a neighbor that she was concerned about his behavior, The Age reports.

Locals in the town have told journalists that the father of two was kind and polite, but then, during the COVID pandemic, his behavior became erratic and his views more extreme.

Freeman - born Desmond Christopher Filby - developed a public profile for his views on the health crisis. He refused to wear face masks in shops, rejected vaccinations, and became increasingly outspoken about his distrust of the government restrictions and lockdowns - of which Victoria had particularly long and strict ones.

Australian media reports that Freeman describes himself as a sovereign citizen, who typically believe they are immune from government rules. The movement saw a particular boom during the COVID lockdowns of 2020.

In 2021, Freeman was involved in an attempt to have then-State Premier Daniel Andrews tried for treason.

Freeman was arrested outside a court in Victoria, where around 250 anti-government protesters had assembled. In a video of his arrest, he can be heard telling the crowd: They're gonna make some [expletive] up about me mate, because I stood up to them.

The treason case was thrown out.

Police say they understand he is an experienced bushman, which presents a challenge for the search party hunting for him; they have warned Freeman is heavily armed.

The family has lived in the Porepunkah area for many years and were known around the small community. Mali teaches music to children and works at a supermarket.