A person has been airlifted to Auckland City Hospital in a critical condition after sustaining a head injury in Whangārei.
In a statement, police said the person, referred to as a pedestrian, received serious injuries in an incident "involving a blue Holden motor vehicle".
It happened around 4.20am on Rawhiti Street in the suburb of Morningside.
A 37-year-old man has since been arrested and charged with reckless disregard for the safety of others caused grievous bodily harm.
He was expected to appear in Whangārei District Court later today.
Now, police are seeking witnesses to the incident.
"We would like to hear from anyone who was in the area at the time and may have witnessed the incident," the statement said.
People with information, or CCTV on Rawhiti Street, were asked to call police on 105 or go online, using Update my Report.
The reference number is 230305/3359.
"Information can also be provided anonymously via Crime Stoppers on 0800 555 111."