A 77-year-old man was rushed to hospital in a critical condition after he was hit by a car in Uxbridge Road, Hayes on Monday (January 16).
Emergency services were called to the busy road at around 6.25pm after reports of a traffic collision.
The pensioner was taken to a west London hospital by London Ambulance Service and police say he remains in a critical condition.
His next of kin have been informed.
The Metropolitan Police said the driver stopped at the scene and is helping with enquiries.
No arrests have been made at this time.
Detectives from the Serious Collision Investigation Unit at Alperton Traffic Garage are appealing for any witnesses that did not contact police at the time to come forward.
Anyone who witnessed the collision is asked to call the witness appeal line on 020 8543 5157 or by tweeting @MetCC. You can also call Crimestoppers anonymously on 0800 555 111.
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