British sprinter Bianca Williams said she had “never had to experience anything like this” after being stopped by police.
Williams and her partner Ricardo dos Santos have accused the Met Police of racial profiling and acting violently toward them.
“It’s a really sad world that we live in and if it’s not one black man, it’s another black man,” a tearful Williams told BBC.
Williams said she and Dos Santos are considering legal action.
“It was just weird that we were treated that way and what hurt me the most was me being dragged away from my son.”
Williams, 26, and Portuguese 400m record holder Dos Santos, 25, fear they were targeted because they are black and drive a Mercedes.
Police say the vehicle had been on the wrong side of the road and the driver sped off when asked to stop.
However, Williams insists “at no point did we drive on the wrong side of the road or speed off.”
“My partner got dragged out of the car, they handcuffed him and pinned him up against the wall... I didn’t want to be separated from my three-month-old son and they then put me in handcuffs straight away too,” she said.
“It’s just nasty and the police were talking to him as if he was scum.”
The couple say police handcuffed them while their three-month-old son was in the car and carried out a search for 45 minutes. Video of the incident showed them protesting that they had done nothing wrong and Williams screaming “my son is in the car.”