A man in his 50s was taken to hospital in a serious condition after being hit by a car in Acton.
Police were called to reports of a collision between a pedestrian and a car at around midday on Monday (June 8).
A spokesman for the Met said: "We were called at 11.56am to reports of a road traffic collision between a car and a pedestrian at Park Royal in Western Avenue.
"The victim (pedestrian) was a male in his 50s. He was taken to hospital in a serious condition.
"No arrests have been made at this time."
This is the second road accident reported in the borough in the last two days.
A motorcyclist was also taken to hospital after a crash with a car, in Greenford, on Sunday evening (June 7).