London (AFP) - British police have apologised to sprinter Bianca Williams for the "distress" caused by a stop-and-search operation they carried out in London.
A video of the incident, which saw the athlete and her partner Ricardo dos Santos pulled from their car on Saturday, was posted online by former Olympic gold medallist Linford Christie.
Williams has said she believes officers racially profiled her and Dos Santos -- a Portuguese 400-metre runner -- when they were handcuffed and separated from their three-month-old son.
London's Metropolitan Police have voluntarily referred themselves to the police watchdog, despite two reviews by the force finding no misconduct by its officers.
Metropolitan Police commissioner Cressida Dick told a committee of MPs on Wednesday: "We apologised yesterday to Ms Williams and I apologise again for the distress this stop clearly caused her."
She said: "Yesterday, two of my officers spoke on our behalf to Ms Williams, and I think all of us watching could empathise with somebody who is stopped in a vehicle, who has a young child in the back, who does not probably know what exactly is going on, and is subsequently found, together with her partner, not to be carrying anything illicit."
Nothing was found in the search, which the Met said was carried out by officers patrolling the area in response to an increase in violence involving weapons.
The force also said the vehicle was seen driving suspiciously, including on the wrong side of the road, and that the driver sped off when asked to stop.
But this account was rejected by European and Commonwealth 100m relay gold medallist Williams, who has said she is considering legal action against the police.
"I feel very hurt by their actions, and to witness my partner being taken away and for me to be taken away from my son, my heart hurts," she said.
Independent Office for Police Conduct regional director Sal Naseem said the watchdog would be looking at whether the use of stop and search was "appropriate and proportionate".
He added: "We will also investigate if racial profiling or discrimination played a part in the incident."