The crash happened at the Lodge Avenue flyover (credit: TfL)
Two lanes are closed at the Lodge Avenue flyover, above the blue light roundabout, following the accident on the westbound carriageway.
Vehicles are using the entry slip road to get around the crash.
Congestion is building very quickly, with traffic queuing back towards the M25 junction.
Time 107.5 has contacted emergency services to find out more information.
