An air ambulance has landed in the grounds of Southborough High School Surbiton after an incident near the A3 at Hook.
A London Ambulance spokeswoman said paramedics were called to Hook Rise North at about 4.45pm to treat a woman reported to have fallen from a height.
The woman was treated for leg injuries and taken by an ambulance as a priority to St George's Hospital in Tooting.
It is not clear if the incident is connected to a reported crash on the A3 involving a motorbike.
All traffic was stopped from 5pm to 5.40pm in the northbound underpass of the A3 at Hook.
Lanes are now open but there is severe traffic and major delays.
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