Hawke's Bay's largest vegetation fire of 2020 was a 400ha fire in Tangoio Forest that started on January 6.
It took 11 days and 300 people, including numerous helicopters and planes, to put out the blaze.
Wild fire investigating officer Donald Scott classed the 2020 fire as accidental and said the most likely cause of the fire was carbon particles expelled from a defective exhaust system on a Komatsu D65EX-12 bulldozer owned by Hawke's Bay logging company K & S Beard Logging.
There is no known cause as yet of the fire on Tuesday.