Firefighters are dampening down a large area of scrub today after a farmer's burnoff flared out of control in the Far North yesterday.

Firefighters and a helicopter crew fought for several hours to before bringing the blaze at Mangamuka, southeast of Kaitaia, under control late yesterday afternoon.

The alarm was raised after a passerby spotted the blaze about 2.30pm.

Fire Service spokesman Colin Kitchen the fire said began after a farmer's burnoff to clear scrub got out of control.

The farmer did not need a permit because it was still an open fire season and he was not within a kilometre of conservation land.

The fire burnt through more than 100 hectares.

- NZPA