A 25-year-old unemployed Dunedin man who last night stole a car while children, aged one and three, slept in the backseat, found himself headed for the Dunedin District Court today.

He faces charges including driving with excess blood alcohol, unlawfully taking a motor vehicle and dangerous driving.

The car owner, who was making a purchase at a Dunedin petrol station, thought his travelling companion was still in the car when it was stolen at 10.20pm.

It was not until he turned to leave the shop that he realise his friend was no longer in the car, but in the queue behind him.

The car was seen driving erratically from the service station.

Police were told the stolen car hit speeds of up to 150kmh before crashing on State Highway 1, south of Saddle Hill overbridge near Mosgiel, south of Dunedin.

The children were unharmed. It appeared that the driver was unaware they were in the vehicle.

"It was extremely fortunate that these children were safely restrained in the child restraint seats given the speed, road conditions and subsequent crash," Dunedin central acting senior sergeant Tania Baron said.

"There could have been a much more serious and tragic outcome."

The driver cut his face in the crash, but did not require medical attention.

- © Fairfax NZ News