Mr Osmond said the person who called 111 informed them there were two people inside the building.
One body, believed to be that of a man, has been found.
But emergency services called off a search for a second person thought to be trapped inside the blaze, he said.
"Everyone has been accounted for so there's no further issues."
He said a full investigation of the fire will be carried out.
No details for the dead man were available, he said.
Sergeant Dave Litton of the Waihi Police said it was too early to tell if the cause of fire was suspicious.
The man's death has been reported to the coroner.