Police are appealing for public assistance following an armed robbery in Lalor last month.

It is believed the victim, a taxi driver, picked up an unknown man on Flinders Street, Melbourne on Friday 20 May about 12.30am and was asked to drive to the intersection of Edgars and Franklin road, Lalor.

When they arrived at the destination the man pulled out a firearm and demanded money from the victim.

He then pulled money from the victim’s top pocket before searching through a bag on the floor of the taxi.

The man then fled on foot, travelling west along Franklin Road.

No one was physically injured during the incident.

Detectives from the Whittlesea Crime Investigation Unit have released images of a man they believe may be able to assist them with their enquiries.

The man has a distinctive tattoo on his left hand.