The owner of the Ranolf St Superette was threatened with a tomahawk before chasing his attacker 500m down the road.
The owner, who does not want to be named, said a Maori man with curly hair, aged about 18, entered his store yesterday afternoon armed with a tomahawk.
"He walked in and stayed by the counter for 10 or 15 seconds.
"I was the only person in the store but he did not know my wife and daughter were in the other room.''
He said he was unaware the robber was armed and was caught by surprise when the man turned towards him pulling out a weapon from behind his jersey.
"He came in behind the small counter, looked at me and held it [the small axe] up in the air.