At approximately 1am two men broke into a bakery in Edgeware by breaking the door with a sledgehammer.
The men targeted two tills before leaving the shop after being confronted by a staff member. The staff member was not injured in the incident.
It is not yet been established what was taken.
The men are described as tall Caucasian, wearing dark clothes and balaclavas.
Police are investigating the robbery and ask anyone with any information to come forward.
Information can be given to Christchurch Central on (03) 363 7400 or anonymously to Crimestoppers on 0800 555 111.
Issued by Police Media Centre