A man in his 60s is in a serious condition in hospital following a crash which closed the A2 for more than six hours.

Both carriageways were closed to allow the air ambulance to land following the accident on the coastbound section near Ebbsfleet at about 4.20pm yesterday.

The crash involved a blue Audi A4 and a black Infiniti M35h but it is thought other as yet unidentified vehicles may also have been involved.

Drivers were left in queues stretching back eight miles while police and ambulance crews cleared the road and treated the victim, who was taken to King's College Hospital in London by land ambulance.

The road did not reopen until shortly after 10pm.

Police are appealing for anyone who saw the moments leading up to the crash to contact them. They are also asking for anyone with dashcam footage to come forward.

Police spokesman Martin Very said: "Officers are working to establish the circumstances of the incident and are urging anyone who saw the cars in the moments leading up to the collision, or who has dashcam footage from the area around the time, to contact them.

"They would also like to hear from any drivers who were involved in the collision and have not yet spoken to a police officer."

The London-bound side was reopened just before 6.30pm once the air ambulance had left the scene.

The coastbound section remained closed until about 10pm, although traffic which had been trapped on the carriageway was released past the scene at around 7.30pm.

Witnesses can call the Serious Collision Investigation Unit on 01622 798 538 quoting 25-1172.

Alternatively they can email sciu.td@kent.pnn.police.uk.

Read more: All the latest news from Dartford

Read more: All the latest news from Gravesend