Two men made off with cash from an armoured van after assaulting a security staff member in Christchurch this morning.
Police said the incident happened in the car park of the McDonald's near Christchurch Airport about 11.40am.
An undisclosed amount of cash was taken.
Detective Damon Wells said it was lucky no one was hurt during the robbery.
"Police and the security company are supporting the staff targeted in this incident."
Inquiries to locate the robbers were ongoing.
Anyone who witnessed the incident, or saw a white Volkswagen parked in or leaving the car park about 11.40am, was asked to call Christchurch police on 03 363 7400.
Information can also be provided anonymously by calling Crimestoppers on 0800 555 111.
Police are urging people involved in transferring money to remain vigilant and report any suspicious activity.