Residents in the Ōtautahi suburb of Woolston continue to be warned to stay indoors as toxic smoke billows from a burning heap of cars at a scrap yard.
Explosions could be heard throughout Christchurch as a huge blaze broke out late on Wednesday night.
At its height, 18 fire trucks and 50 firefighters were on scene fighting flames that were six storeys high.
Fire and Emergency New Zealand (FENZ) said the blaze has been contained to the main car pile but cordons would remain in place for most of the day as crews worked to keep it under control.
Canterbury Fire and Emergency assistant commander Mike Bowden said the fire remains contained but is expected to continue burning for some time.
He said firefighting efforts have been successful in reducing the significant fire at the scrap yard.
Currently, there are three appliances, a specialist aerial unit, 16 firefighters along with three diggers pulling the pile apart to aid in the dampening down of this fire.
Bowden said environmental efforts continue to ensure the runoff into the nearby Heathcote River is either stopped or contained.
"Booms were put in place on the river and sucker trucks are being used to drain any runoff," he said.
In an earlier update on Thursday afternoon, FENZ assistant commander Dave Berry said six firetrucks and 30 firefighters remained at the scene.
"This will be a long duration incident and firefighters are expected to be on the scene throughout Thursday."
Berry said residents and businesses in the immediate vicinity were still being encouraged to keep windows and doors closed and stay inside, due to potentially toxic smoke.
Those calls were being echoed by the Asthma and Respiratory Foundation.
"It is great to hear that this fire is now under control but I understand there is still a lot of smoke coming from the site," foundation chief executive Letitia Harding said. "Smoke is a major trigger for asthma and can worsen existing respiratory conditions.
"Please keep any respiratory medications nearby and if you experience a flare up of your condition, contact your health professional as soon as possible."
Earlier, Christchurch residents from around the city had reported seeing the blaze.
The nearby Christchurch Bull Breed Rescue centre on Wednesday night evacuated all of its dogs.
"Thank you Christchurch City Council for coming to our rescue and housing our dogs at extremely short notice," the rescue said.
The cause of the fire remained unknown.
