Detectives from Box Hill Embona are investigating an armed robbery which occurred in Box Hill in August.
Investigators have been told the 25-year-old victim from Box Hill had arranged to meet two men on Monday August 19 about 9.20pm on Station Street to purchase a car.
They agreed to go to a local church car park to complete the transaction.
On the way one of the men made a phone call, telling the person on the other end of the line where they were headed.
When they arrived at the car park on Oxford Street the group was approached by two other men.
The victim was then seriously assaulted by the four men and his backpack, which contained cash for the purchase, was stolen.
The offenders left the scene and the victim was taken to hospital with serious injuries.
Investigators have released images of two men who they believe can assist with their enquiries.
Investigators are appealing for anyone with information to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au