Officers tried to pull over a black Mercedes, which was being driven "erratically", an hour before Maynard's body was found on the tracks.
At approx 4.15am on Monday, 18 June, officers stopped a vehicle after it was seen being driven erratically in Arthur Road, SW19.
The male driver of the vehicle - a black Mercedes C250 - made off on foot.
Officers were unable to locate the man.
At approx 5.10am the body of a man fitting the same description was found on tracks near Wimbledon Park station.
The force added that it was still trying to identify the man found on the tracks and that the Directorate of Professional Standards and the Independent Police Complaints Commission have been informed.
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