Black smoke billowing from a fire on View Rd in Rotorua can be seen from as far away as the CBD.
A Fire and Emergency NZ spokesman said a fire at a commercial building on View Rd was reported about 12.30pm.
The two-storey building, which is about 20m by 30m, was well involved when crews arrived, he said.
There are five fire crews at the scene and another two on the way.
There was nobody inside the building and no reports of injuries, he said.
The fire was not currently at risk of spreading to other buildings.
A bystander has described the fire as "in full swing".
"I just heard some loud pops... then went outside and saw the fire was in full swing," he said.
The bystander said the fire was "burning really hot" and there was "tonnes of black smoke".
One Rotorua resident said he could see the fire from CBD while another could see the smoke from Harumana, on the other side of Lake Rotorua.
A police spokeswoman said there were police at the scene assisting with traffic control.
Traffic was being diverted at View Rd's intersections with Old Taupo Rd and Riri St.
More to come.
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