Police are calling for information after a man wielding a firearm and making demands for cash fled a Braybrook service station empty-handed on November 2.
It is believed the service station attendant grabbed a hammer after being approached by the man who demanded a plastic bag be filled with cash at the Ballarat Road store about 10.30pm.
He was last seen running along Ballarat Road towards Sunshine.
Police have released images of a man whom they believe may be able to assist them with their enquiries.
He is described as Caucasian, between 40 to 45 years old and 178cm tall with a medium build.
He was wearing a black peaked cap with a red ACDC logo, a grey chequered hooded jacket, green t-shirt, blue jeans and white runners.
Anyone with information can contact Crime Stoppers on 1800 333 000 or visit the Crime Stoppers website.