The NZ Transport Agency advises motorists that State Highway 1 is closed due to a serious crash north of Pūhoi.
Motorists should be aware there will be delays and they should avoid the area if possible.
Those travelling north or south into or out of Auckland city they are advised to use SH16 where possible.
A detour is in place between Silverdale and Warkworth in both directions.
The detour will add an expected hour to your journey.
The road is expected to be closed for some time while Police Serious Crash Investigators are on site.