Police are investigating an aggravated robbery in the Northland town of Ruakaka

Police say a man entered the GAS Service Station on State Highway 1 Ruakaka about 25-past-seven last night (7.25pm), with a firearm.

He demanded cash and cigarettes from the attendants, before running off to a vehicle parked at the northern end of the service station and drove off.

The offender was heavily disguised, carrying a black backpack which he used to store the stolen goods.

Police are appealing for any witnesses to the robbery.