Police have issued a witness appeal after two people sustained head injuries in a motorway crash.

Emergency services were called at 1.40pm on Saturday following the collision between a silver Mitsubishi Pajero and a blue BMW 118 Sport, on the coastbound carriageway of the M2 at junction 3, near Walderslade.

A man and woman from Gravesend who were passengers in the Mitsubishi were airlifted to a London hospital with head injuries, and another man in the same vehicle received minor injuries.

Officers from the Serious Collision Investigation Unit are appealing for any witnesses who have not yet spoken to police to call the Serious Collision Investigation Unit on 01622 798538 or email sciu.td@kent.pnn.police.uk quoting reference MM/MR/107/15.

Reece Chandler, 27, from Walderslade, captured the scene on camera and tweeted photos, posting: "Just saw this 10ft in front of me. I witnessed the whole thing."

He said he had just pulled onto the M2 at Walderslade when he saw a silver 4x4 leave the outside lane and hit the central reservation.

"The silver 4x4 was in the fast lane, next to him was a blue BMW, and I was just behind in the slow lane," said Mr Chandler, who is unsure exactly how the accident happened.

"I don't think he was speeding, I think a tyre blew out. He tried to turn himself back into the main road, but at that point he lost all control, the car went sideways and he was rolling and flipping.

"It was like a scene out of a James Bond film. It was the most horrific thing I've ever seen.

"A piece of debris had smashed the driver's window of the blue BMW, but he managed to pull over."

Mr Chandler, who was travelling with his two children, called emergency services and is in touch with the police.

He believes the driver of the 4x4 sustained life-threatening injuries, while two other passengers - a woman and a man - were less seriously injured.

"I've never witnessed anything like it," he added. "It's shocking. I've had to meet up with my friend for a drink."

Huge delays built up on the coastbound section between Junctions 3 and 4, in the aftermath of the crash.

Both carriageways were closed to allow the air ambulance to land and take off. All lanes reopened just after 7pm.

Some motorists caught up in the delays reported drivers using the hard shoulder, blocking ambulances from getting to the crash scene.

@cricketlin tweeted "People seem patient at the moment even though it's hot."

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