According to police, one person was taken to hospital with serious injuries after the robbery.
Ash Parmar, a local business advocate and fellow retail store owner, said the worker got chased to the back of the shop during the robbery when his fingers were sliced off with the machete.
The worker lost his index finger and thumb, dairy owner Puneet Singh told Stuff.
According to police, officers were "following lines of enquiry to locate the offenders and hold them to account".