Police are investigating the armed robbery of a Chinese restaurant at Frenchs Forest last night.

About 10.45pm (Friday 30 March), four males armed with weapons confronted the employees of the restaurant on Sorlie Road at closing time.

Two of the offenders entered the business through the front door, while the other two entered through a rear laneway.

The balaclava-clad males stole cash from the till and other personal items before escaping out the rear laneway.

A 63-year-old man and 59-year-old woman were injured after being struck by the offenders.

They were taken to Manly Hospital for treatment of minor injuries.

A 49-year-old woman and 16-year-old boy who were also inside at the time were not injured.

There were no customers inside the restaurant.

Police established a crime scene which was examined by officers from the Forensic Armed Robbery Unit.