A motorcyclist has been rushed to hospital in a serious condition after a collision with a lorry in Streatham High Road.
London Ambulance Service said the man was taken to hospital with pelvic injuries which were not believed to life-threatening.
Paramedics were called to the incident by the junction with Heybridge Avenue near Streatham Common at 8.58am.
The London Air Ambulance was also dispatched but the motorcyclist was taken to St George's Hospital in Tooting by road ambulance.
Police said a white Ford Iveco truck was involved in a collision with a silver Honda Motorcycle.
Road cordons have put into place and buses have been diverted.
Simon Fowle, of A & J Fowle Antiques, said the southbound lanes of Streatham High Road were closed causing lengthy tailbacks.
No arrests have been made.
Police are still at the scene.
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