Police are urging the driver of white SUV involved in a hit and run west of Kaikohe on Friday night to come forward.
Kerikeri police Senior Sergeant Peter Robinson said the crash occurred about 6.20pm on State Highway 12, near Taheke, as one vehicle heading west went to overtake another.
The driver and passenger of the overtaking car allege the other vehicle swerved across the centre line, causing a collision.
The overtaking car then spun around and crashed into a bank.
The other vehicle, a white Mitsubishi Pajero or similar, did not stop but continued west towards Hokianga.
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The female driver of the car, aged 32, was airlifted to Whangārei Hospital along with a three-year-old girl as a precaution.
A 37-year-old male passenger and another girl, believed to be 2 years old, were also in the car.
Senior Sergeant Steve Dickson, the head of Northland road policing, urged the person driving the other car, or anyone who knew who it was, to call police on 105.
The car which did not stop was likely to have damage to the front right-hand side.
St John Ambulance and the Kaikohe Fire Brigade also responded to the crash.