Two drivers were thought to be "racing" each other before one of their vehicles crashed on Auckland's Southern Motorway and forced the closure of an on-ramp.
Police confirmed the single vehicle crash occurred in a northbound lane at around 12:20pm on Saturday near the Orams Rd overbridge in Manurewa.
"From speaking with those at the scene, police believe this crash to have resulted from two drivers racing each other."
One man was taken to hospital as a precaution and police have spoken with the driver of the second vehicle.
Police are still making enquiries, but believe traffic-related charges are likely to be laid.
The New Zealand Transport Authority tweeted the Hill Rd on-ramp had been closed. Drivers carrying out essential travel were asked to avoid the area or follow directions of the on-site emergency services.
Police didn't say whether any charges would be related to the alert level 4 lockdown restrictions, of which, as of Thursday, there had been 4452 total breaches.