Detectives from Embona Robbery Taskforce are investigating following two armed robberies earlier this week.
It is understood a male offender attended a service station on Fitzgerald Road, Laverton north about 3.45am on 21 October. About ten minutes later, he attended a service station in Geelong Road, Brooklyn.
It is believed he moved between the two locations in an unknown vehicle.
During each incident, he produced a metal pipe and threatened the attendant before making demands for cash and cigarettes.
Both attendants refused and he left each store empty handed.
No one was physically injured during the incidents.
The male police wish to speak with is perceived to be Caucasian in appearance and was wearing a distinctive Oakland Raiders black hoodie, black Adidas shorts with white stripes down each leg, dark runners and a dark cap under the hood of his jumper.
Investigators are appealing for anyone who saw the male or with information to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au