A scrub fire in Waihi quickly took hold due to dry conditions in the area.
Waihi fire chief Moe Stevens said the brigade was called to a large patch of bamboo, grass and gorse which caught alight on the side of State Highway 2 near Rifle Range Rd about 1.40pm yesterday.
About 12 fire fighters, two trucks and a tanker were needed to fight the blaze which was 500m-600m long and about 50m wide, he said.
"It was a fairly big area. Of course a lot of smoke was going across the road which doesn't do the traffic any good."
Mr Stevens said there was no way to know how the fire started.
"Everything of course is tinder dry. It could've been a cigarette butt, it could've been a piece of glass. They are just a couple of possibilities."
In such dry conditions the magnification of the sun through a piece of glass on the right angle can be enough to cause a blaze, he said.
"That's the first major sort of scrubby we've had. Things are just absolutely ready to go."