One person is likely to face prosecution and others face hefty bills after four Far North fires in less than 48 hours.
The biggest blaze, near Omanaia in South Hokianga, burned about 3ha of scrub and native bush on Tuesday afternoon.
The fire, on a bush-clad hillside, could not be reached by ground crews so was extinguished by a helicopter using a monsoon bucket.
Northern principal rural fire officer Myles Taylor said the blaze appeared to be an "accidental escape" rather than malicious.
There were no fire restrictions in the area as yet so the fire-starter would not be prosecuted, but he would have to pay the firefighting costs, which were likely to be substantial. Operating a helicopter costs at least $2000 an hour.