The latest in a series of suspicious fires in Papamoa has left an iwi organisation "gutted and absolutely shattered".
Police are investigating the blaze at the offices of Mangatawa Papamoa Blocks Incorporation on Tareha Lane after residents raised the alarm about 11pm on Tuesday.
Firefighters stopped the fire spreading to the main office areas but a wooden deck and the side of the building were extensively damaged.
Mangatawa Papamoa Blocks chairman Kevin Haua said he believed the fire was deliberately lit and suspected the fire could be related to other suspicious fires in Papamoa late last year.
"We're gutted and absolutely shattered that someone would stoop to this level and do this to us, " he told the Bay of Plenty Times.
"There appears to be some bad people running around lighting fires in the area. That hasn't been proven yet."
Detective Sergeant Alan Kingsbury confirmed the fire was suspicious and said police were investigating.
But it was too early to say whether the fires were connected, he said.
The blaze is sixth suspicious fire in the Papamoa area - including the Papamoa Hall which burnt down in late October and a fire that caused more than $2 million damage to the Tauranga Eastern Link fly-over.
Mr Haua said he initially feared the organisation's records would be lost in the fire but the fire brigade was "just fantastic".
"When we got up there we were quite relieved to see a lot of the offices were undamaged.
"It's a blimmin' set back for us. We've got to find somewhere else."
The organisation employed four people who worked from the office every day.
"They are working out in the barn at the moment. It's a real setback. I feel sorry for the ladies in the office. They are gutted."
It was the organisation's second major setback after a major hailstorm damaged its kiwifruit orchards in November.
Papamoa fire chief Allan Bicker said the spate of suspicious fires in October and November seemed to have stopped, which came as a relief especially considering how dry conditions were.
He doubted the latest fire was linked to the earlier ones.
Papamoa Progressive Association chairman David Hill said the community was concerned.
"There has been a number of suspicious or hard to explain fires which in a dry period could be anything from a careless cigarette butt," he said.
"With three or four times the population there's a lot more people moving in and out of the area. It would be disappointing if there were locals involved. I would suspect not.
"People are concerned about this sort of stuff as a community should be," he said. "When something like this happens it is exceptionally noticeable."