Four people taken to hospital after inhaling toxic fumes at a Tauranga coolstore have been allowed to return home.
About 20 cleaners were exposed to an ammonia leak at a mussel processing plant on Friday night before it was contained by the Fire Service.
Four were taken to Tauranga Hospital but a spokesperson says they have bee discharged with no serious injuries.
The Fire Service says the plant has been closed until the source of the leak can be located.
It was called to the North Island Mussel Processing site on Glenlyon Avenue shortly after 8pm.
Fire communications says a hazardous substances unit and four fire trucks attended the scene, with officers wearing protective gas suits.