Two motorcycles and a car have been involved in a serious crash near the Kaipara Harbour northwest of Auckland City.
At least one person has been injured in the crash, which happened on State Highway 16 near Ogle Rd at around 2.50pm.
Few details are available yet.
The police said the ambulance service and the Westpac Auckland rescue helicopter were responding to the crash.
NZTA reports the road has been closed, and urges motorists to please avoid SH16 if possible.
Cordons have been placed on roads and the Serious Crash Unit has been notified.
SH16 MANGAKURA - CRASH - BOTH DIRECTIONS - 3:00PM
ā Waka Kotahi NZTA Auckland & Northland (@WakaKotahiAkNth) January 29, 2018
A serious #crash on SH16 near Mangakura is blocking traffic in both directions. The road has been closed so please avoid SH16 if possible. A detour has been put in place. ^JF pic.twitter.com/BK4YycEpJ7