The 72-year-old man who was hit by a bus in Hayes on Saturday (March 11) remains in critical condition three days after the collision.
Police were called to Printing House Lane near the junction with Botwell Lane at around 3.45pm after the incident and the pensioner was flown to an east London hospital by air ambulance.
His injuries are being treated as life threatening and his family have been informed.
The E6 bus stopped at the scene and the Metropolitan Police said the driving was assisting with enquiries.
Officers launched an appeal for witnesses on Saturday night and are asking for anyone who can assist their investigation to contact them.
There have been no arrests in relation to the collision.
Anyone with information is asked to call the witness line on 020 8991 9555.
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