Fire investigators have confirmed that a serious blaze south of Kaikohe was deliberately lit.
The blaze on Mangakahia Rd, Tautoro, threatened two homes and a large block of native bush on Tuesday afternoon.
About 20 firefighters from Kaikohe's fire brigade and rural fire party, plus three helicopters using monsoon buckets, managed to confine the fire to about 4ha of scrub.
It started just over 24 hours into a Far North fire ban and was the district's third suspected arson in three days.
Northern principal rural fire officer Myles Taylor said the investigation had revealed the fire started not by the roadside as first suspected, but near some well-used tracks within the scrub.