A car ripped a petrol station bowser from the ground before crashing into a Burger King building in South Auckland this morning.
The incident occurred about 4.30am on Bader Drive in Mangere.
Four ambulance crews attended and four occupants of the car were taken to Middlemore Hospital with moderate to serious injuries.
Inspector Willie Taylor said alcohol and speed were contributing factors.
The car came off Bader Drive about 30 metres before crashing through the BP station into the adjoining Burger King and catching fire, he said.
An investigation by Serious Crash Unit is under way.
"There were some lucky escapes there.
"There's apparently quite a bit of damage and debris around there so it's worth investigating, and then establishing who the driver is so we can follow up."
Three fire crews attended because of the oil spill and one team was still there "mopping up", Fire Service shift manager Jaron Phillips said.
"We're just washing down, using absorbent, and mopping up the oil spill. They shouldn't be there for too long," he said.