Five people have been treated by ambulance staff after a reported refrigeration gas leak at Countdown in Grey Lynn.
The supermarket was evacuated shortly after 1pm and four fire trucks were called to the scene.
St John Ambulance confirmed five people were assessed at the scene but a spokesperson for Countdown told 3 News only two employees were treated and both have returned to work.
Countdown Grey Lynn is currently being renovated and the Department of Labour has been called to investigate.
The supermarket reopened an hour after the incident.