Police are appealing for witnesses following an armed robbery at a Deer Park shopping centre last year.

Investigators have been told the victim exited the Neale Road shopping centre about 11.10pm on Thursday, September 14.

He was approached by an unknown man, who engaged in a brief conversation.

During the conversation a second masked offender appeared and struck the victim to the head with a solid object.

A third offender then appeared and produced a hand gun, pointed it at the victim and demanded cash.

A quantity of cash was stolen. The offenders ran off through an adjoining reserve towards Oakwood Road.

The primary offender is perceived to be Pacific Islander/Maori appearance, about 185-190 centimetres tall, 25 to 30-years-old and was wearing a distinctive blue and white coloured hoodie.

Detectives from Brimbank Embona Taskforce have released images of a man they believe may be able to assist with their investigation.

Anyone with any information is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report at www.crimestoppersvic.com.au