Fire and Emergency says four homes had to be evacuated during a fire next to State Highway 1 in Northland's Brynderwyn Hills on Friday afternoon.

Wildfire specialist Rory Renwick said the blaze, which raced through a hectare of grass and scrub, was brought under control around 5pm by six fire trucks and a helicopter.

Firefighters would be working from the side of the highway for a few more hours as they put out all remaining hot spots, he said.

Travellers should continue to take alternative routes around the Brynderwyns if possible, he said.

It is not yet known what started the fire just before 3pm.

This story was originally published by RNZ