A fatal crash has prompted the closure of State Highway 1 near Kaiwaka, north of Auckland.
Photo: RNZ / Richard Tindiller
Emergency services were notified about 1.40pm that a car and truck had collided.
St John said it had sent two ambulances, a first reponse unit, a primary response doctor and a helicopter.
Police confirmed one person had died at the scene.
Another person had been airlifted to Whangārei Hospital with moderate injuries and someone with serious injuries had been taken there in an ambulance.
St John said a third person with moderate injuries was treated at the scene.
Fire crews and serious crash investigators are also on site.
The Transport Agency said the crash happened near Settlement Road in Kaiwaka.
The road is closed for a 12km stretch - between Kaiwaka-Mangawhai Road and at Mangawhai Road Te Hana.
Motorists are being asked to detour via Mangawhai, which takes an extra 30 - 40 minutes, or delay their journeys.
The Transport Agency said the road was likely to be closed for some time.