A driver has died in a crash at the speedway in Palmerston North.
Emergency services were called to the track at about 6.15pm.
Eyewitness accounts onine said that the victim was a driver.
The Superstock Teams Champs event is being held this weekend, and is one of the city's biggest events of the year.
Racing for the rest of tonight and tomorrow were called off.
"As per the announcement over the public address system, we were advised not to continue tonight's meeting," the speedway organisers announced online.
"What a sad day for NZ speedway," a racing fan posted on Facebook.
Thousands of racing fans and drivers were expected in the region.
Worksafe has been notified, and the police will investigate on behalf of the Coroner.