Shortly before 2pm, Inspector Peter Raynes of Tāmaki Makaurau Police said a police vehicle had spotted a car travelling at excess speed along Great South Road in Penrose, Auckland, and signalled for it to stop.
It failed to do so and instead fled, crashing with two other cars, Raynes said.
The driver of the vehicle which allegedly failed to stop was transported to hospital in a critical condition.
One person from one of the other vehicles died at the scene, while another was also critically injured.
Another person was in moderate condition.
Raynes added the Serious Crash Unit was examining the scene, and the road remains closed.
A 'Critical Incident Investigation' had been launched, and staff were working to establish the full circumstances surrounding the crash, he said. They are working to support those affected and their families, as well as the staff who were involved.
The incident has also been referred to the Independent Police Conduct Authority.
