A person is being cut out of their car by firefighters after it collided with another vehicle on State Highway 16, near Kumeu.
Northern fire communications shift manager Jaron Phillips says crews came across the 12.41pm crash - between Kumeu and Waimauku - as they were making their way back from a house fire in nearby Kaukapakapa.
Mr Phillips says after stumbling across the crash, firefighters called police and St John Ambulance staff to the scene.
They are now trying to free one of the occupants, who has suffered moderate injuries, with the jaws of life.
Mr Phillips was unsure how badly traffic will be affected by the crash but expects some delays as the scene is cleared.