Fire communications spokesman Colin Underdown said five appliances attended the scene and said the fire affected two shops and was spread over an area 50m by 10m.
There was a large amount of smoke when firefighters arrived at the scene at 3.39am, he said.
A fire investigator at the scene this morning said two stores were damaged by fire and several others were damaged by smoke but she did not know yet how many.
The co-owner of Bula Takeaways was in tears speaking to a Rotorua Daily Post.
The Fijian speciality takeaway shop had been there since June last year and was gutted by the fire.
Co-owner Ashmi Reddy said their daughter got a call this morning from a friend who said their shop was in trouble and they went straight over.
She said the owner of the Four Square told her it had started from a rubbish bin and his bin had been set on fire twice before.
She said four bins usually sat under a window which had a wooden board over it. This morning there wsere three with remnants of a charred wheel visible.
She said the bins were full of cardboard which would have burned and potential caused the windows to catch fire.
"We just have to wait for everything to clear...but we will carry on."