Emergency services were called to the incident in Olympic Ave about 12.15am.
A 32-year-old woman was flown to Melbourne’s Alfred Hospital and remains in a critical condition after being run over by a car, which left the scene after striking the woman.
Shepparton Criminal Investigation Unit Detective Sergeant Jeff Wren said investigators had recovered a Holden Commodore sedan believed to be involved in the incident, near Wunghnu, south of Numurkah.
He said the identity of the driver was not yet clear and inquiries were continuing.
Meanwhile, a 40-year-old man was taken to hospital with non-life-threatening injuries after an alleged assault and has since been released.
Det Sgt Wren said some items had been recovered near the scene of the alleged assault but it wasn’t yet clear whether they were related.
He said police believed the hit-and-run and alleged assault were connected, given they took place close to each other.
Three men and a woman were assisting police and have been released pending police inquiries.
“We’re working around the clock; we’ve put a lot of effort into this and while we are progressing it’s always good to get further information from the public,” Det Sgt Wren said.
Anyone who has any information or dash-cam footage of the incident or saw the vehicle is urged to phone Shepparton Criminal Investigation Unit on 5820 5800 or Crime Stoppers on 1800 333 000.