Boubacar Drame was helping a mother find her lost daughter when three police officers approached.
One said a few words. The second took Drame to the ground - and knelt across his throat.
Drame is 31 years old, worked at town hall at the time, and is a Black Frenchman. This is a Paris suburb.
The incident led to an ongoing police internal investigation, but Drame believes, there's been little in the way of answers or accountability so far.
"When I was on the floor, they crushed my head then my throat and my chest and stomach. Then I felt a pressure between my legs, I thought he hadn't done it on purpose but as I saw he was doing it insistently I knew it was intentional. So I screamed. People where coming around us so in desperation I asked them to film as I thought maybe that would put them off.
"At that time I felt totally powerless. They were crushing me, I couldn't do anything. I found it hard to breathe properly. They were hurting my private parts. They inflicted all kinds of abuse..."
Drame says he had no idea why he was being detained, other than he matched the profile of a suspect they were hunting.
He was released after the town mayor and police chief intervened. He worked as a community mediator for the town.
Drame filed a complaint with prosecutors.
"Among the things they told me, there were things which were totally discriminatory. They told me 'I am used to guys like you'. What does that mean? What does he mean by 'guys like you'?"
It's now a year on from Drame's detention.
And though the streets of Gennevilliers are far from Minneapolis, the pain felt across the world over the killing of George Floyd resonates.
The ordeal has left him psychologically scarred.
A doctor ordered him on sick leave for three months.
Paris police said they could not comment on an ongoing investigation.