MOTORISTS travelling out of Kent face long delays following a collision involving two lorries that resulted in a fuel spillage.
The crash happened at around 2.20pm close to the exit of the tunnels between junction 31 and 30 of the motorway in Essex.
An Essex Fire and Rescue Service statement said one driver was trapped and crews took two sets of specialist cutting equipment to release him.
As a result of the diesel spillage, the motorway is expected to remain closed overnight for resurfacing.
An Essex police spokesman said: "Only one of the two lorry drivers was injured.
"He is a man in his 20s.
"He was airlifted to hospital and received multiple injuries."
The spokesman added: "Motorists who are trying to enter Essex from Kent are being diverted off at Junction 31 to rejoin the motorway further ahead.
"The anti-clockwise carriageway at the crash scene is not expected to open until the early hours of Tuesday morning (December 18)".
Essex Travel News said on Twitter that Traffic is back towards Junction four in Orpington.