London police said on Monday it had voluntarily referred itself to the conduct watchdog after armed officers stopped the car of a Black athlete in the capital for a second time.
Portuguese 400m runner Ricardo dos Santos was stopped in the early hours of Sunday by officers on a routine patrol who said they were concerned about a driver possibly using a phone at the wheel.
"The officers clearly indicated for the car to pull over but it failed to do so and they called for further assistance," the Metropolitan Police said in a statement.
