A 42-year-old man remains in a critical condition in hospital after a crash on the A4 Great West Road in Hounslow.
The crash on Monday night (October 2) between a Bentley Continental and Vauxhall Corsa forced the road to close overnight as emergency services including London Air Ambulance, London Ambulance Service and the Metropolitan Police attended.
Police were called to the scene at around 10.40pm and closed the road between Bath Road and Upper Sutton Lane.
At this early stage, Met officers believe the Bentley had been racing a third car when the crash occurred.
The 42-year-old Vauxhall driver was taken to a central London hospital in a critical condition while the 30-year-old Bentley driver was taken to a west London hospital but later discharged.
The Bentley driver was then arrested on suspicion of causing serious injury by dangerous driving and taken to a west London police station.
Detectives from the Met's Roads and Transport Policing Command are investigating and are keen to speak with anyone who may have witnessed the crash.
Anyone with information is asked to contact the Serious Collision Investigation Unit on 020 8543 5157 or police via 101 or via Twitter @MetCC.
The road reopened to traffic at around 5am on Tuesday (October 3).
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