An unmarked police car had just started following a black Seat driving at speed moments before it crashed in the city outskirts.

Despite the police vehicle not being involved in the collision, the incident in Thorpe Road has been referred to the Independent Office of Police Conduct (IOPC), which deals with complaints and conduct matters involving officers.

A spokeswoman for Norfolk police said this is "standard procedure”.

The crash, which happened in the early hours of Thursday morning, resulted in the driver of the Seat being taken to hospital with serious injuries.

The aftermath of the crash in Yarmouth RoadThe aftermath of the crash in Thorpe Road (Image: Newsquest)

Jlulel Rezin, who lives in Thorpe Road with his wife and young child, heard the collision.

He said: "We could hear the sound of an exhaust coming from the Norwich direction towards the junction with Harvey Lane.

"We heard the brakes screeching and a loud crashing sound.

"We knew it was bad just from the sound of it."

Jlulel could see debris from the car scattered on the roadJlulel could see debris from the car scattered on the road (Image: Newsquest)

He added: "I ran outside immediately, and police officers were already there.

"The car was completely destroyed. It had no wheels left on it but remained upright.

"I could see that the car was full of smoke.

"I ran over and helped the police officer get the doors open and someone was still inside the car. He then called an ambulance and for more police officers.

"It was terrible."

Debris is littered along the edge of the roadDebris is littered along the edge of the road (Image: Newsquest)

The police spokeswoman said: “At 12.44am an unmarked police car was patrolling in Norwich when they noticed a Seat Leon driving at speed.

"The officers turned their vehicle around and started to follow the Seat which proceeded to drive through a red light.

READ MORE: Road closed for eight hours after police incident

"Before officers could attempt to stop the car, it collided with street lighting on Thorpe Road, near to the junction with Harvey Lane."

The roadsign was knocked down in the crashThe roadsign was knocked down in the crash (Image: Newsquest)

The road was closed while emergency services attended the scene, including fire crews and the ambulance service. It reopened just after 9am that morning.

The police spokeswoman added: "The driver of the Seat, a man aged in his 20s, was taken to Norfolk and Norwich University Hospital with serious injuries. He has since been discharged.

"Enquiries are ongoing to understand the full circumstances which led to the incident.

"No arrests have been made so far."