A neighbouring resident, just across the road from the blaze, described a smell of burning plastic before rushing outside to see emergency services at a scene filled with black smoke.
Bruce Ferguson said he was looking around his house to try and find out where the smell was coming from before discovering the scene of the fire across the road.
“We were just inside, and I could smell burning plastic, and I was looking around the house to try and find out what it was, and I came out the front, and there were two fire trucks and an ambulance.
Ferguson said he did not know the residents at the address.
Emergency services were alerted to the fire in at about 5.20pm on Sunday and a person was found dead inside the building, police said.
A Fire and Emergency New Zealand spokesman said when crews arrived the building, which measured about 15m by 9m, was “well ablaze”.
The spokesman said Fire and Emergency services were called to the fire at about 5.19pm. Two fire trucks and one support vehicle were dispatched to the incident.