State Highway 1 is closed near the Northland township of Mata after a fatal crash.
It is expected to cause further delays for motorists travelling between Auckland and Northland, after the highway was closed through the Brynderwyn Hills and a detour route was blocked when a logging truck rolled.
A person died at the scene following the Mata crash, which happened about 2.33pm between Totara Road and Hewlett Road, police said.
"Police extend our condolences to their family and friends at this time."
A second person had been taken to hospital with serious injuries.
The state highway had been closed in both directions.
"Motorists are advised to expect delays, or to avoid the area if possible," police said.
SH1 MATA - ROAD CLOSED -3:10PM
— Waka Kotahi NZTA Auckland & Northland (@WakaKotahiAkNth) February 26, 2024
Due to a serious crash a section of #SH1 is now CLOSED between Mata & Oakleigh. Allow extra time for the detour. More: https://t.co/uzFIKZeAaK ^HJ pic.twitter.com/G5csgyOKT0
Diversions were being put in place between Springfield Road and Salmon Road.
The serious crash unit was examining the scene.
Monday marked the first day of the closure of State Highway 1 through the Brynderwyn Hills for restoration work after damage caused by Cyclone Gabrielle.
Just after midday Monday, a detour route - Paparoa-Oakleigh Road through Mangapai - also had to be closed after a logging truck rolled.
Drivers were told to expect extensive delays, with light vehicles urged to detour through Waipū Cove and trucks told to use State Highway 12 through Dargaville.
Paparoa-Oakleigh Road was reopened just before 5pm.