Victoria Police said the 58-year-old woman had been arrested in the Bairnsdale area on Friday and would be interviewed by Taskforce Summit investigators.
She is one of several women police have sought over who helped Freeman, 56, after he murdered the two officers and attempted to kill another two on August 26 last year.
Police have raided multiple properties in NSW as part of the investigation, suggesting the killer may have been harboured interstate for at least some of the time before he was gunned down in northeastern Victoria on March 30.
Police have said they will not comment further because the deaths are before the Coroner; the arrest does not mean the woman is guilty of any offence.
“Detectives from Taskforce Summit arrested a 58-year-old NSW woman in the Bairnsdale area this morning as part of their ongoing investigation into the movements of Desmond Freeman following the fatal shooting of two police officers in Porepunkah last August,’’ police said in a statement.
“The woman will now be interviewed by police.
“The investigation remains ongoing and as such, we are not in a position to provide further details at this time.”
Bairnsdale is about 240km south of Porepunkah, where the police were murdered by Freeman.
One theory is that Freeman was spirited away from near the scene of the crime soon after it was committed and as police attempted to rally after the murders.
Last month four of the raids chasing Freeman’s helpers were in NSW, a state Freeman had visited many times, including on holidays with his children.
NSW raids were conducted at Greenwich Park near Goulburn, at nearby Tarlo, Wombeyan Caves near Bowral, and Umina Beach on the Central Coast.
Last month Victoria Police also executed warrants at three rural properties at Buckland, near Bright in northeastern Victoria, nearby Stanley, and at Lucyvale, south of where Freeman was killed by special operations police.
The Victorian police operation is called Taskforce Summit, while the NSW police aspect is part of Strikeforce Namberta, with a total estimated cost of tens of millions of dollars.
Freeman was gunned down on March 30 after he refused to surrender at a property at Thologolong near the Murray River, east of Albury.
The police decision to intensify the pursuit of collaborators comes as NSW is now playing a larger role than first thought, with Freeman likely to have fled as far north as the Central Coast, before being shot dead on the NSW-Victorian border.
Details of Freeman’s final hours and the Porepunkah killings were aired recently in the Victorian Coroners Court, where an inquest into the deaths of two police officers was heard alongside a separate inquest into his fatal police shooting.
The Porepunkah inquest heard that Freeman shot Detective Leading Senior Constable Neal Thompson in the face after the officer had breached Freeman’s makeshift home outside Porepunkah, about 300km northeast of Melbourne.
Freeman then took Senior Constable Vadim de Waart-Hottart’s service handgun after shooting him in the head from behind, using it to fire again at Thompson when he was already dead.