A worker nearby said he heard a “bang” when the car hit the pedestrian and then the sound of sirens a short time later.
Another person said the road was “filled with police cars”.
Botany Rd is now closed between Millhouse Dr and Golfland Rd.
The spokesperson said the police are investigating the crash to determine its cause.
Police are urging motorists to use alternate routes as road closures may be in place for some time.
A Hato Hone St John spokesperson said they took one person to Middlemore Hospital in a serious condition.
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