Motorists are at a standstill on the M23 following an eight-vehicle crash earlier this morning (February 15).
Thousands of vehicles have been stuck in queues of traffic for more than four hours due to the collision which took place between junction 9, to Gatwick Airport, and junction 8, to the M25, at 10.45am.
One person is believed to be seriously injured whilst another suffered minor injures, police said.
Officers closed all three carriageways after diesel spilled onto the road.
An eyewitness said police were continuing to turn around northbound traffic but thousands of vehicles were still stationary.
Long queues are also being reported as far back as the Pease Pottage roundabout.