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.