Hagley College in Christchurch has closed for the day due to the smoke from a nearby car workshop fire.
Firefighters believe the blaze, which broke out just before 4.30am at Auto Inspection Services on Colombo St, Sydenham, spread from a pile of waste and general rubbish.
However, it is not yet clear how it started.
In a post on Facebook, Hagley College said the decision to close the school was made because of the smoke.
"Year 9 & 10 students will be heading to Gym 2 and will be released upon a message from home being sighted."
In its noon update, Fire and Emergency NZ said one firefighter was injured and transported to hospital for observation.
"We are providing them with support," a Fenz spokesperson said.
A text alert was issued this morning by Fenz to residents and businesses in Sydenham, Addington and Spreydon advising them to remain indoors if possible due to the smoke.
"If you have any health concerns please call Healthline or 111 in an emergency."
Fenz incident controller Dave Key said the large fire was contained. Up to 50 firefighters and 10 fire engines battled the blaze this morning.
Key said they now know the fire began in a pile of waste and general rubbish but are still investigating what caused it.
However, some roads around the workshop were closed for most of the day.
"Cass St is still closed. The pedestrian walkway on the left side of Colombo St is also closed off," a Fenz spokesperson said.
"Smoke is still continuing to drift across Colombo St, so please take care as you drive and always keep your eyes on the road.
"Smoke will continue to drift across the city, so continue to keep your windows and doors shut if you are being impacted by the smoke.
Fire crews remain at the scene and will be using heavy machinery to turn over debris to stifle the fire.
That may mean the smoke will be coming and going throughout the day.
