A man has been arrested over the disappearance of Samantha Murphy.

There's been an arrest in the case of missing Ballarat woman Samantha Murphy.

Victoria Police provided the update this morning, saying a 22-year-old Ballarat man was arrested at about 6am on Wednesday at his home.

He is yet to be charged as of Thursday morning, and remains in custody.

In a statement, Victoria Police said: "Despite a significant investigation and extensive searches of the Canadian Forest area, no trace of the 51-year-old [Samantha Murphy] has been located.

"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."

The 51-year-old mother of three left her home at Eureka Street in Ballarat East on February 4 to go jogging and has not been seen since.

Police say it's unlikely that Victorian woman, who disappeared in suspicious circumstances, will be found alive.

She was last seen wearing black half-length leggings, a maroon or brown singlet and an Apple Watch. Investigators are asking residents in the area to review their CCTV footage from between 7:00am and 11:00am on February 4 for sightings. 

With AAP.

Feature Image: Supplied/Facebook.