Fire Service crews from around Hawke's Bay battled the scrub fire from about 1.30pm at Poraiti near Taradale.
The scrub fire was brought under control by about 5pm.
Mr Nicholl said fire services would remain on-site for the next 12-18 hours to make sure it was put out properly and there were no more flare-ups.
He said changing wind conditions had made firefighting difficult and the fire at times changed direction as it moved up the hillside.
Three helicopters using monsoon buckets helped firefighters on the ground to subdue the flames.
Four houses in Oak Rd were evacuated as a precautionary measure and residents are now being allowed back into their homes.
Police had been on standby to evacuate more homes in close proximity to the fire if necessary.
Smoke from the fire had spread across some Napier suburbs and the central city and prompted numerous calls to police and the Fire Service.
It is not known how the fire started at this stage.