Police are appealing for witnesses, or anyone with dash cam footage, to come forward following a fatal crash on the Princes Highway.
A 47-year-old female motorcyclist was involved in a collision with a car, near Forsyth Road, about 4pm on Friday.
The Kilmore woman was taken to hospital but died later that night.
The vehicle allegedly left the scene following the collision.
Police arrested a 45-year-old man at a Wyndham Vale address on Friday evening. The man was interviewed and has been released pending further inquiries.
Witnesses or anyone with dash cam footage of the collision can contact Crime Stoppers on 1800 333 000.