A teenager is understood to be among four people injured in a serious crash that left the vehicle involved a twisted and mangled mess.
Emergency crews were called to the corner of Great South Rd and Ronwood Ave, in Manukau, shortly before 3.30am.
A New Zealand Fire and Emergency spokesman, Scott Osmond, said they were needed to help get a number of people out of the vehicle.
"The car was on its roof and three people were trapped."
Fire crews used rescue equipment to release those trapped. He said at least two people were seriously injured.
Police said just after 6am that the road was blocked off as a result and motorists are being told to avoid the area. The Serious Crash Unit has also been advised.
All lanes were re-opened by 7.30am, the NZ Transport Agency said.
Images of the scene show debris littered over the road and kerb not far from the Westfield shopping centre. The front of the car is completely smashed in and up against a tree.
Several ambulance vehicles and authorities could be seen blocking the road as they worked at the scene.
St John said four people were injured - two seriously. Two suffered serious injuries and the others were said to be in a moderate condition when taken to hospital.
It is understood one of the victims is a teenager and has been taken to Starship Children's Hospital for treatment. The others have been taken to Middlemore Hospital.
Meanwhile, a person was seriously injured in another car crash in Mt Roskill about the same time.
St John said the victim was taken to Auckland City Hospital for treatment.