Police are appealing for information following an armed robbery in western Sydney yesterday evening.

About 5pm (Wednesday 16 March 2016), a man entered a business on Church Street, Parramatta, and threatened the attendant with a firearm while demanding cash.

He fled the shop on foot a short time later, with cash, and was last seen running south on Church Street.

No one was injured during the incident.

Officers attached to Parramatta Local Area Command were alerted and launched an investigation.

A crime scene was established at the business, and examined by detectives and specialist forensic officers.

Police are continuing their inquiries into the incident and would now like to speak to a man who may be able to assist in the investigation.

The man is described as being of Asian appearance, about 25-30 years of age, around 170cm tall and of a thin build.

He was last seen wearing a black t-shirt, cargo shorts, glasses and a black hat.