Police have carried out sting operations to crack down on illegal sales of nitrous oxide for recreational use - known as nangs.

Five retailers across the North Island have been charged under the Psychoactive Substances Act and could face prison time.

The canisters are meant to be used to whip cream.

Superintendent Dion Bennett says during the stings - it was clear customers were buying nangs for recreational use.

"We weren't dressed as bakers, we didn't represent ourselves as home bakers - it was obvious that we weren't there to buy nitrous oxide for baking purposes." 

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