Emergency services are responding to a serious two-car crash on SH1, Pohuehue, between Puhoi and Warkworth.
Police were called about 5pm.
Initial reports are there have been injuries.
The road is expected to remain closed in both directions for some time and motorists should expect extensive delays.
Diversions will be in place.
Anyone travelling northbound or southbound in the area is advised to take SH16 as an alternative route.
Motorists should also consider delaying travel, if possible.