The rail line between Whangārei and Auckland is closed after two wagons derailed on Monday.
KiwiRail General Manager Operations Upper North Island Reuben Araroa said wheels on two wagons on a freight service travelling towards Whangārei derailed between Kaiwaka and Te Hana.
''Staff are currently on site re-railing the wagons, assessing any track damage and developing a repair plan,''Araroa said.
''It is too early to comment on causes, how long the line will be shut, or the cost of any repairs.''