A motorcyclist has been flown to hospital after a serious crash which closed the A21 for almost five hours.

The crash, on one of the busiest travelling days of the year, happened at about 9.30 this morning.

It coincided with hundreds of bikers heading towards the coast for their annual May Day Run to the Hastings 1066 motorbike event.

Both London and coastbound carriageways were shut by police to allow the Kent Air Ambulance helicopter to land.

A spokesman for the South East Coast Ambulance Trust said: "We sent two ambulances and a response car to attend. The air ambulance also attended.

"Our crews treated a single patient, an adult male, at the scene for serious injuries.

"He was then taken by air ambulance to King's College Hospital, London."

Highways England set up a number of diversions but many motorists were still left stranded on the A21 Tonbridge Bypass between the A26 Quarry Hill Road and A26 Woodgate Way.

The London-bound carriageway was opened shortly before 1pm and the coastbound section was reopened at about 2.15pm.

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