A 49-year-old man died when his Mazda collided with a white Toyota Landcruiser on Boyd Road, near Williamson Road, Gordonton, about 10.15am.
The driver of the Toyota, who was seriously injured, may have had a dispute with the driver of a white Audi A3, police said.
Detective Inspector Darrell Harpur said the Audi left Horsham Downs Primary School at 10am and was followed by the Toyota.
He understood the cars were speeding and trying to overtake each other.
Both cars drove at speed up Boyd Road and as the Toyota attempted to overtake the Audi, it collided with the Mazda.
Harpur said the investigation into the crash was complex, and police wanted to hear from anyone who witnessed any dangerous driving on these roads between 9.45am and 10.15am.
Police were also interested in any dashcam footage, security footage or other imagery of the vehicles.
RNZ
