Ms Williams was speaking at a police misconduct hearing into the incident - footage of which subsequently went viral.

She and her partner, Ricardo Dos Santos, who is also an international athlete, believe they were racially profiled by the Metropolitan Police.

Dashcam footage played at the hearing showed the pair being followed in their Mercedes by police to their west London home from training in July 2020.

They were then handcuffed and searched for drugs and weapons by officers after they were pulled over outside their property - nothing was found.

Their three-month-old son was in the back seat of their Mercedes throughout the encounter.

Ms Williams, 29, a gold medallist in the 4x100m relays at the 2018 European Championships and Commonwealth Games, wept as she watched the footage at the hearing.

It showed officers pulling Mr Dos Santos from the driver's seat and taking him to the roadside where they handcuffed him.

A tearful Ms Williams could be heard in the footage telling police: "My son is in the car - I need to look after him."

Moments later, she too was handcuffed as one of the officers suggested the couple had "antagonised" the police and may have "something to hide".

At one point in the footage, the infant can be heard screaming as the officer leaned into the back of the car to "check around the baby seat" before allowing Ms Williams to collect her son.

Nothing was found, and the couple were released shortly after.

Read more on Sky News:
Five police officers could face sack over stop and search

On Wednesday, Mr Dos Santos, 28, a Portuguese competitor in the 400m sprint at the Tokyo 2020 Olympics, told the hearing he was not trying to "evade" the police and was not driving dangerously.

"I didn't want anything to happen to my family and I wanted to get home," he said.

"I was afraid for the safety of Bianca and my son."

He claimed he had been left "traumatised" by several encounters with police who stopped him without reason.

The five police officers involved could be sacked if gross misconduct is established.

All five are accused of breaching police standards over equality and diversity.

Four face allegations that their actions amounted to a breach of professional behaviour standards in relation to the use of force.

They are also accused of failing in relation to their levels of authority, respect and courtesy, as well as in their duties and responsibilities.

The officer who was driving the police vehicle is accused of breaching professional standards in the way he carried out his duties and responsibilities or gave orders and instructions.

The five deny the charges and the six-week hearing continues.