Victoria police have arrested a 22-year-old man in relation to the disappearance of missing Ballarat woman Samantha Murphy, who vanished more than one month ago.

Murphy, 51, was last seen at about 7am on 4 February, captured on CCTV footage in her family home’s driveway. She had told friends and family members she planned to go for a run.

Victoria police on Thursday said a Ballarat man was arrested at about 6am on Wednesday. He remained in custody and no charges have been laid at this time.

“Despite a significant investigation and extensive searches of the Canadian Forest area, no trace of the 51-year-old has been located,” police said in a statement.

“We understand that there is a continued high level of interest in this investigation and concern about Samantha’s disappearance, however it remains critical that any speculation does not impede any aspects of the investigation.”

Police last month revealed they suspected “one or more parties” were involved in the disappearance of Murphy, saying it was “very doubtful” she was still alive.

Acting Det Supt Mark Hatt had previously said there was nothing to indicate that Murphy left the area of her own accord and ruled out a medical incident.

Mobile phone data provided a new lead in the search for Murphy, with detectives returning last month to a previously examined area in the Mount Clear area – about 7km south of her home – for a targeted hunt for clues.

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