A man believed to be carrying a handgun has been shot and killed by police following a car crash.

Police were called to the A11 at Thetford, Norfolk at about 20:35 GMT on Sunday when a man, believed to be the driver of one of the two vehicles, left the scene holding what was described as a handgun.

Armed response officers attended and the suspect was subsequently shot by police from "a short distance away". The force said that despite the efforts of emergency services, he was pronounced dead at the scene.

Following the incident, the A11 London Road remained closed in both directions and diversions are in place.

Norfolk Police said it had made a "standard procedure" referral to the Independent Office for Police Conduct (IOPC) following the incident.

The force's Assistant Chief Constable David Buckley said: "We understand this incident will cause concern in the community.

"Our highly trained armed officers deploy to hundreds of firearms related calls each year, but incidents where police discharge firearms are thankfully incredibly rare. A full and independent investigation is already underway.

"We are of course cooperating fully with the IOPC investigation and will be handing over all body-worn footage and 999 calls to ensure transparency.

"We are not looking for anyone else in connection with the incident."

An IOPC spokesperson confirmed it has started an independent investigation.

In a statement they said: "We were notified by the force after the incident on the A11, at Thetford, near the exit for London Road, just before 9:40pm and declared an independent investigation a short time later.

"Despite the man receiving treatment for his injuries, he sadly died at the scene.

"We sent investigators to the post-incident procedure to begin our enquiries and start gathering evidence.

"Our investigation is in its very early stages."

Reporting from the scene, BBC Norfolk's Jack Maclean described how the A11 at Thetford remains closed this morning.

"I'm standing at the Brandon Road roundabout where traffic usually would be quite busy," he said.

"There are a selection of cones and there is a police officer with their lights on sitting in their car blocking the road."

Images from the scene showed forensic officers surveying the carriageway.