Police are appealing for information followed an armed robbery at a Penshurst service station overnight.

About 2.20am (Monday 7 October 2013), a man parked his vehicle at the Forest Road service station, before threatening the attendant with a knife and demanding cash.

The man fled the location a short time later with a sum of money and was last seen driving north on Forest Road.

No one was injured during the incident.

Officers attached to Hurstville Local Area Command attended and launched an investigation.

A crime scene was also established at the location and will be examined by specialist forensic officers and detectives.

Police would now like to speak to a man who they believe may be able to assist with their inquiries.

He is described as being of Caucasian appearance, 25-30 years of age, about 170cm tall, with short hair and a beard. He was last seen wearing a light blue hooded jumper.

The man was also seen driving a dark-coloured car, bearing registration plates similar to BT86BA.

Anyone who may have witnessed the incident or has information that could assist detectives is urged to come forward.