Part of the M25 in Essex has been closed in both directions after a serious collision.
National Highways said emergency services including an air ambulance were at the scene between junction 29 at Upminster and junction 30 at Aveley in Thurrock.
According to traffic monitoring system Inrix, the incident happened on the anti-clockwise carriageway.
National Highways said traffic going clockwise was being diverted, external from junction 29 on to the A127. Whereas anti-clockwise traffic was diverted from junction 30 on to the A13 towards Tilbury.