Police pulled over the car for a routine stop that would end with one officer hospitalised.

A police officer was dragged along the road by a car as it fled a routine traffic stop.

He suffered moderate to serious injuries to his arms and legs during the incident, which unfolded on Harper Ave in Christchurch at about 1.55am on Saturday.

"While police were speaking with the female driver, one of the passengers got into the driver's seat and drove off at speed with the driver's door still open," Christchurch metro area prevention manager Inspector Richard Bruce said.

"One of the attending officers was dragged along as the vehicle drove off before falling onto the ground. He . . . was largely saved from more serious injury by the protective equipment he was wearing."

Police later located and arrested the driver, who was charged with injuring with intent to injure.

He will next appear in Christchurch District Court on October 3.

George Carter, the car's registered owner, was confused when police later tried to contact him – because he had never owned it.

He said police turned up at his parents' home in the early hours of Saturday, asking about a Ford Falcon supposedly belonging to Carter.

Carter was asleep in his university hall of residence and did not answer calls from his family.

"All of a sudden I woke up, and I got like 20 missed calls."

Carter previously worked with the driver, who he said was "reasonably unstable" and prone to anger.

He was surprised to find out from police the man had registered two cars in Carter's name.

Carter also knew one of the passengers of the car, who relayed the whole story to him.

A female had been driving the car, on her learner's licence. The passengers – two males and two females – were drunk.

One of the males, the one who had registered the car in Carter's name, ran off into Hagley Park and hid.

The man returned shortly after, Carter said.

He said the man had taken the car key off the keyring before handing the keyring to the police officer when they were first pulled over.

"[The driver] hops in the car, turns it on and then tries to start to drive. At this point the door's open, all of the other four people are still in the car and then the cop's latching on for dear life.

"And it's not until they got to about 90 [kmh] that the cop actually let go."

The man dropped off three passengers, and took another car – also registered in Carter's name – to Rangiora in North Canterbury to drop the last passenger off.

Carter said he gave a statement to police in the morning, but by then they had already arrested the man.

Police could not comment further because the matter was before the court.