THE London-bound section of the A12 was closed between the Margaretting and Mountnessing junctions after a police car was involved in a serious crash.

The crash happened just after 7.30am today and involved a  London Metropolitan Police car which overturned.

Congestion is occurred back to junction 13 at Ingatestone.

An Essex Police spokesman said: "Two people were in the vehicle. One has been airlifted to hospital with serious injuries."

The road was re-opened shortly after 12 noon.