An organiser of a vintage car racing event says the death of 68-year-old driver in the Waikato is a tragedy.
The police say the man died after his 1961 Cooper open-wheel formula car failed to negotiate a bend and collided with a wall at about 1.30pm on Saturday.
The man was competing at the Roycroft Trophy Vintage Festival at Hampton Downs race track in Waikato.
The chairman of the Waitemata branch of the Vintage Car Club, which runs the event, Ian Bradley, says a medical incident may have been a factor in the crash.
Mr Bradley says the man is well known at the club and it will be offering support to his family.
Senior Sergeant Rupert Friend of the Hamilton District Command Centre says no other vehicles were involved in the crash.
The police Serious Crash Unit is investigating and a video of the incident will be key to establishing the cause of the crash.
St John Ambulance says another driver was taken to hospital with spinal injuries after another car rolled earlier in the day.
Racing was cancelled for the rest of the day.