Senior Sergeant Brian Benn, of Dunedin, said they were called to the aggravated robbery at Lookout Point Food Centre on the corner of Riselaw Rd and Columba Ave about 5pm yesterday.
It appeared a man, described as a solidly-built Maori about 1.8m tall, in his early 20s and wearing a black hoodie and cap, entered the store brandishing an imitation gun, while an accomplice waited in a silver Honda Civic outside.
He demanded cash but was not given any and left the store with only a small amount of tobacco.
Police had tracked the Honda Civic to a nearby location, but wanted to hear from anyone who had seen it travelling at speed about 5pm.
They had CCTV footage of the robbery, but were not ready to make it public.
The store’s owner, who did not want to be named, said a young man came into the shop "grabbed some smokes and just ran away".
The man was brandishing a plastic BB gun, but the experience was not that scary for the shop owner because the gun was so obviously not real.
"The first time I saw the gun I realised it was fake."