FENZ say they will be down-scaling operations at Christchurch's national scrap yard

On Wednesday night, hundreds of wrecked cars were ignited on the Woolston site, with about 55 firefighters and 15 fire trucks attacking the four story blaze.

FENZ say they have the scene under control and are preparing to hand the site back to the owner.

Fire and Emergency group manager Mike Bowden is asking residents stay vigilant as there may still be some smoke coming from the site over the next few days.