A 60-year-old man remains in hospital after being attacked on the Croydon flyover following a car crash on Wednesday morning.
The man, who was fighting for life after suffering cardiac arrest after the collision at 9.45am, is in a stable condition at Croydon University Hospital.
Police arrested a 45-year-old man at the scene on suspicion of causing grievous bodily harm.
He has been bailed to return to a south London police station in December.
Metropolitan Police detectives today appealed for any witnesses to come forward.
Anyone with information can contact Croydon police on 101 or call Crimestoppers anonymously on 0800 555 111.
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