Police are investigating an armed robbery at a service station at Warner early this morning.

Just after 1am, three men armed with knives entered the store on Old North Road.

Two of the men approached the counter and threatened the employee before stealing cash from the register. 

The third man remained near the door to the shop.

The employee was not injured during the incident.

All three are described as being Caucasian in appearance and 18 to 25-years-old.

One man was 177cm tall, average build with dark brown hair. He was wearing a black jumper with white writing on the front and a hood.

The second man was 153cm tall, slim build, sandy coloured hair and wearing a grey jumper with a hood. He also wore black track-suit pants which had a white stripe down the outside of each leg.  

The third man was around 177cm tall, brown hair and wearing a dark blue jumper and jeans.

All men fled on foot and were last seen running north along Old North Road towards Stanley Street.