Detectives in Sydney’s south-west are conducting inquiries following an armed hold-up at a St Andrews petrol station.

Just after 8.15pm yesterday (Friday 3 August 2012), a balaclava-clad man entered the service station on Ballantrae Road and threatened the console operator with a firearm.

The offender stole a sum of cash from the register and then ran from the store.

No shots were fired during the incident and no one was injured.

Police from Macquarie Fields Local Area Command and the Forensic Armed Robbery Unit attended the scene and conducted inquiries.

Investigators are looking at whether the same man might have been involved in another incident at Lurnea two hours later.

About 10.30pm, an employee noticed a man in a balaclava outside a Hill Road pizza shop.

The man – who was holding a firearm – entered the store a short time later, causing the victim to flee out the back.

Officers from Liverpool Local Area Command responded to the incident; however, the offender left the scene before they arrived. Specialist forensics officers examined the crime scene.

Detectives are appealing for public assistance as they try to identify and locate the offender.

He’s been described as being of Caucasian appearance, 180-190cm tall with a large build, and was wearing a black balaclava, blue hooded top, camouflage shorts and black shoes.