Paris police banned a planned protest on Saturday against violence by the force, a week after France was rocked by riots sparked by the killing of a teenager in a suburb of the French capital.
A Paris police department spokesperson said that the planned demonstration on the Place de la Republique had been banned over risks to public order, citing a "context of tensions" after the recent unrest on French streets.
Politicians including President Emmanuel Macron and the French authorities have denied institutional racism within the country's law enforcement agencies.
But since the shooting of Nahel they have come under pressure from rights groups to address allegations of racial profiling by police and questions over recruitment and training.
French police have come under renewed scrutiny following the June 27 shooting by a police officer of Nahel M at a traffic stop. The teenager was driving a sports car without a licence.
Saturday's protest had been called by the family of Adama Traore, a Black Frenchman who died in police custody in circumstances similar to the killing of George Floyd in the United States.
The demonstration against alleged police violence and racial discrimination was initially planned as a march in Beaumont-sur-Oise, another Paris suburb, where Traore died in 2016.
But this had already been banned by the local prefect, citing an elevated risk to public order and security, only days after France was shaken by nationwide riots.
The ban was upheld by a court on Friday, prompting the call for a gathering in central Paris instead. Left-wing leaders including the parliamentary group chief LFI, Mathilde Panot, had said they would join the gathering.
It was not immediately clear whether the organisers would also challenge the new ban from Paris authorities.
A policeman who prosecutors said acknowledged firing a lethal shot at Nahel is under formal investigation for voluntary homicide, equivalent to being charged under Anglo-Saxon law.
His lawyer has said the officer had aimed at the driver's leg but was bumped when the car drove off, causing him to shoot towards his chest, and had not intended to kill the teenager.
