Man threatened with gun in robbery

A man was allegedly threatened with a gun and suffered abdominal injuries during a robbery in Sydney's southwest overnight.

Police are appealing for information after the 22-year-old was threatened with the weapon by one of three men who entered a business property at Mount Erin Road in Blair Athol.

A short time later, the trio allegedly fled the scene in the man's car with cash, as well as the man's wallet.

Officers attached to Campbelltown Local Area Command attended and established a crime scene.

They are appealing for witnesses or anyone with information about the incident to contact them via Crime Stoppers.

The injured man was taken to Campbelltown Hospital and treated for non-life threatening abdominal injuries.

The men are only described as wearing dark clothing and hooded jackets.