A motorcyclist has died after being struck by two vehicles in a horrific crash on a Victorian highway.

It’s believed a red Mazda CX3 collided with a motorbike on Princes Hwy near Corangamite Lake Rd in Colac West just after 11.30am on Sunday.

The motorbike rider, a 40-year-old woman, was then hit by a Toyota Landcruiser.

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She died at the scene.

Both of the drivers stopped and assisted police.

The 77-year-female driver of the Mazda was interviewed by detectives but released pending further investigation.

Police are appealing for anyone who witnessed the collision or has any relevant dashcam footage to come forward and contact Crime Stoppers.