Firefighters used rescue equipment to free one person who was trapped in a car, a Fire Service shift manager said.
A witness said the crash happened at the intersection of Glenfield Rd and Kaipatiki Rd.
She said two people were lying on the ground but at least one appeared to be okay.
"He was moving his legs and arms."
McDonald's Glenfield manager Angeline Apan ran outside as soon as she heard there had been a crash.
The 19-year-old said she saw a student in a Westlake Boys uniform lying on the footpath. Another school-aged boy was lying about 10m further along the path next to a silver car which had mounted the pavement.
The car appeared to have swerved into the pavement to avoid a bus that was trying to park at the bus stop, but the two vehicles had still crashed.
A woman was unable to get out of the car, Apan said.
"I ran out straight away to try and help. A lady at the bus stop was a nurse and she told me to run and get the first aid kit. Then I ran up to the White Cross and got a doctor and nurse to come down, and we both were on the phone to the ambulance," Apan said.
"The guy from Westlake was responding but he said he couldn't move his leg - but he was moving it by the time the ambulance came."
Police said there were "significant blockages" to traffic and drivers were being asked to avoid the area.
The witness believed the car had hit both the bus - which was stationary - and a pedestrian.
Auckland Transport spokesman Mark Hannan said a Birkenhead Transport bus, which is contracted to AT, was involved in the crash.
