Police want witnesses and dashcam footage after a trucker was seriously injured in one of three crashes on the M2.

The first collision happened on the coast-bound stretch between junction 5 for Sittingbourne and 6 for Faversham just before 7am, when a car crashed into the central reservation.

Shortly after, three cars collided in around the same place on the London-bound side.

Then a third crash happened just behind the first incident on the coast-bound carriageway.

It involved a white Mitsubishi Fuso tipper truck and a yellow DAF truck, and left one of the drivers trapped with serious injuries.

Police have since launched an appeal for anyone who saw the third crash, which happened just before 7am, to come forward.

The 25-year-old man who had been driving the Mitsubishi suffered serious injuries and was cut free from his vehicle before being flown to King's College Hospital in London.

Both vehicles had been approaching the scene of the earlier crash when they collided.

Traffic was held while the air ambulance landed, and vehicles were diverted off the motorway at junction 5.

The helicopter remained on the scene for around an hour before taking off just before 9am.

A woman, who was involved in the first crash, was also treated by paramedics before being taken to Medway Maritime Hospital with injuries thought to be minor.

The London-bound side had reopened by 9.10am, but it took two hours for delays to clear.

Coast-bound remained closed until around 12.30pm while an investigation was carried out and debris cleared from the road.

Drivers trapped in the tailbacks reported chaotic scenes, with people getting out of their cars and vehicles travelling down the hard shoulder in the wrong direction to escape the queues - including one that nearly hit a fire engine.

Police warned motorists to remain in their vehicles for their own safety while emergency crews dealt with the incidents.

A spokesman said: "Officers and South East Coast Ambulance Service are at the scenes of three collisions on the M2 between junctions 5 and 6.

"Kent Police was called at 6.50am on Monday 11 September 2017 regarding a report that a car had collided with the central reservation of the coastbound carriageway between junctions 5 and 6.

"The driver of the car was treated for injuries that are described as minor and her vehicle was moved to the hard shoulder.

"A second collision involving three vehicles was also reported in the London-bound carriageway at the same location. No injuries have reported at this stage.

"A third collision involving two trucks was then reported in the coastbound carriageway prior to the first incident. The driver of one of the trucks has injuries that are described as serious.

"Officers ask that the occupants of vehicles held in the queue do not get out and walk in the carriageway. Drivers are also asked to keep the hard shoulder clear for emergency services."

Witnesses or anyone with dashcam footage of the third crash is asked to call the appeal line on 01622 798538 quoting reference 204/17, or email td.sciu@kent.pnn.police.uk