Officers from Brimbank Embona are appealing for information following an armed robbery at a Deer Park service station on Boxing Day.
Investigating detectives believe the man attended the store on Ballarat Road, armed with a knife, on Monday 26 December about 2am.
Once inside the store the man leaned across the counter and had a conversation with the attendant before he removed a knife from his jumper.
The man then made demands for cash and threatened the life of the attendant.
The store attended handed over a quantity of cash from the till before the offender fled. He was last seen walking down Station Road.
Police have released CCTV and images of a man they believe can assist with their enquiries.

The man is described as having a media build and facial hair.
He was last seen wearing a green, blue and red hooded windcheater, which was pulled up over his head, a beanie, thongs and cargo or similar pants.
Anyone with information or dashcam footage is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.auExternal Link