The M25 anticlockwise is blocked with stationary traffic and long delays between J30 A13 (Lakeside / Tilbury) and J29 A127 (Romford), congestion to J1a A282 / A206 Crossways Boulevard / B3228 (Swanscombe).
A second air ambulance is attending the accident on the clockwise side and there are long delays whilst all traffic is held anticlockwise.
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Britain has seen its hottest ever Halloween with temperatures breaking records for the last day of October.
A gallery of your ghoulish pumpkin creations.
It will stay mild this evening and overnight with clear spells eventually giving way to showers by the morning.