"Police began following the driver at a distance and after a time, signalled for the driver to pull over but they failed to stop and a brief pursuit was initiated," she said.
"A short time later the fleeing driver crashed at the intersection with Cascades Rd and the vehicle ended up on its roof."
The spokeswoman said all six occupants were teenage girls.
The girls were checked over by St John Ambulance staff following the crash and would all be referred to Youth Aid.
A witness described the car as "a mess" with a crumpled roof and shattered windscreen.
"It looks like the car had been driving along Pakuranga Highway away from town and it hit a street sign and rolled."
At least two people were rushed away in an ambulance, the witness said, while others were speaking to police following the incident.
