The driver died at the scene.
While the officer was taping off the road, a gold-coloured 2000 Honda CRV station wagon allegedly sped past, hitting the officer in the leg before driving off from the scene. He was treated for minor injuries including bruising to his foot.
The car, stolen from a home at Lara last week, was later found dumped in a creek off Cuthbertson Road in Corio at around 8am this morning.
It is not believed to be connected to the earlier fatal crash.
Police spent hours examining the car, dusting for fingerprints and collecting evidence including cigarette butts.
Security vision from nearby factories was also gathered.
Detectives believe the runaway driver is aged in his late teens, Caucasian in appearance, with long hair, and was wearing a hoodie.
“I was horrified, absolutely horrified,” Acting Inspector Monique Leffanue said.
“It’s absolutely concerning and that’s why we are putting all of our resources towards it to find out who this person is”.
Anyone with information is urged to contact Crime Stoppers on 1800 333 000.