Writing on Instagram, Mr Richards said he had complained to the Metropolitan Police and the police watchdog about what he called “racial profiling” in the incident, in the early hours of 4 September.
The actor said: “In a flash, I was face-down on the pavement with multiple officers holding me down, forcing my head into the ground.
“I couldn’t see anything, but I could hear my mum nearby, screaming and crying, begging them to let me go.
“That feeling of helplessness will never leave me. The whole experience was embarrassing, deeply upsetting, and exhausting.
“I won’t rest until I’ve gotten to the bottom of this and I am deeply saddened for anyone else who has been through this.”
He added: “I do everything I can to avoid interactions with the police, yet this experience has made it painfully clear that racial profiling remains a significant issue.”
