A woman has been left with serious injuries after a hit-and-run collision at Noble Park in Melbourne's south-east.
Emergency services received reports of a female pedestrian who had been hit by a white van while crossing Heatherton Road near Avon Street at about 7pm on Saturday.
Detective Sergeant Stephen Hill said an eastbound white-coloured van struck the woman and failed to stop at the scene.
"It beggars belief why, but the driver of the van continued, leaving the 34-year-old female dying on the road side until the ambulance arrived," he said.
Witnesses helped the Springvale woman, who was later taken to the Alfred Hospital with life-threatening injuries.
"Police are extremely interested to speak to the driver of the white van," Detective Sergeant Hill said.
"The van will have substantial front passenger-side damage, with a number of pieces left at the scene.
"I'd like to think that every member of the Victorian community, if they struck a person on our road, would stop and render assistance.
"Why you would leave someone dying on our roads without rendering them assistance?
"This lady is someone's daughter, someone's partner and she's been left lying and dying on the side of the road."
Investigators have urged the driver of the van to come forward to police.
"We will catch you," he said.
Anyone with information or dashcam footage has been urged to contact CrimeStoppers.