A scrub fire is causing delays to motorway traffic near the Puhoi tunnel, outside Auckland.

Police and fire fighters are at the scene, where the blaze is burning along the motorway just north of the tunnel.

The motorway has not yet been closed and traffic is still moving but smoke is causing delays, police said.

Motorists are advised to take extra care and avoid the area if possible.

The Puhoi tunnel is on the Northern Gateway Toll Road north of Auckland.

– APNZ