The trucks' tires aren't designed to go more than 100km/h.
Many buildings were lost, including the town's favourite Indian restaurant.
Auckland motorists may have to wait after the four-vehicle collision.
It happens when people under stress experience physical symptoms, but the cause is psychological.
There are reports people were seen running away from the blaze.
Investigators are working to determine whether the blaze is suspicious.
Crews are starting to assess roads and remove debris on Monday morning.
Ngongotaha locals are now being moved to a safe place for the night.
But others aren't so sure, and want more information.
More than 500 firefighters are still battling the 1000-hectare blaze.
It could take another day to fully extinguish the blaze.
Three people have been hospitalised with smoke inhalation.
Three helicopters and 10 ground crew are fighting the blaze.
Two have been left in a serious condition after what police have called "fighting and disorder".