Hopes CCTV leads to Ristevski breakthrough

Police have released CCTV footage of what they believe is murdered Melbourne mum Karen Ristevski's car, as they confirm her husband is a suspect.

Inspector Tim Day says police are hunting cars seen near what could be Karen Ristevski's car, pictured, on the day she went missing - June 29, 2016. Source: AAP

Police have confirmed Melbourne mum Karen Ristevski's husband is a suspect in her murder, as they hunt drivers seen near what could be her car on the day she went missing.

CCTV cameras captured what police believe is Ms Ristevski's black Mercedes-Benz SLK coupe heading northwest over train tracks in Diggers Rest about 11.12am on June 29, 2016.

Ms Ristevski, 47, was reported missing the next day, after she was last seen at her Avondale Heights home by her husband, Borce Ristevski.

The vision was captured from a train station and shows the Mercedes following several other vehicles, including a white ute towing an excavator on a trailer.

Missing Persons Squad Inspector Tim Day wants to eliminate any possibility that the two-seater Mercedes seen in the footage belonged to anyone else.

Of the hundreds of black Mercedes-Benz SLK coupe owners spoken to by police, fewer than 20 are yet to be contacted in Victoria.

"We've still got a little bit of work to do to eliminate any other cars, certainly in the state of Victoria," Insp Day told reporters on Friday.

Earlier this year, Mr Ristevski's lawyer told Fairfax his client was a "prime suspect" in the case.

Insp Day confirmed Mr Ristevski is a suspect, but would not say if anyone else is being considered.

"I'll take out the word prime and say yes, he is a suspect," he said.

The black coloured Mercedes Benz SLK coupe seen in the area where Melbourne mother Karen Ristevski was last seen. Source: AAP

"I'll leave others to judge as to what makes him a suspect, but all I will say at this stage is yes, he remains a suspect into the death of Karen."

Insp Day says he is confident the Missing Persons Squad will find the killer.

"Ultimately the person who's done this has a story to tell and generally only get one chance to tell it. I encourage them, if they're so inclined, to tell it now," he said.

Police believe the Mercedes-Benz was driven through Diggers Rest on to Gisborne and then past the Mount Macedon Golf Club towards Macedon Regional Park, where Ms Ristevski's body was found on February 20.

Insp Day told reporters he believes only one person was in the car at the time the CCTV was captured.

Mr Ristevski has told police he took his wife's car out for a drive on June 29 but did a u-turn and returned home.

"I'm aware that's what his version of events are," Insp Day said.

Two weeks after Ms Ristevski's body was found, Mr Ristevski served as a pallbearer at his wife's funeral and the couple's daughter Sarah led the procession carrying a framed photo of her mum.