The spokesman said the fire is being treated as suspicious and a specialist fire investigator has been called to the scene
It was the fourth of five calls answered by firefighters in the Napier-Hastings in less than 90 minutes.
The first was at 9.12am to a car fire in Wakefield St in Napier's Onekawa industrial district, but the fire was extinguished by the time a crew arrived.
Two calls were to single-vehicle crashes in Hastings, the first at 9.30am after a vehicle overturned in Richmond Rd and the second reported at 10.12am in Heretaunga St West. The last of the calls was at 10.30am to Cortes Cres, Flaxmere, where a FENZ spokesman said a street electricity "box" had ignited, also setting fire to a fence.