Human rights watchdogs, including the Council of Europe, criticized French police for using excessive force during protests against President Emmanuel Macron's pension reform.
French authorities arrested more than 450 people on Thursday in the most violent day of demonstrations since the start of the year against the bill to raise the retirement age from 62 to 64.
In the days leading up to Thursday's protests, rights groups had expressed worries over "arbitrary" detentions and the excessive use of force by police.
But security officials have defended their actions, saying they are responding to violent rioters and anarchist groups who they claim frequently infiltrate French demonstrations to provoke clashes.
France's Human Rights League has accused the authorities of "undermining the right of citizens to protest by making disproportionate and dangerous use of public force."
"The authoritarian shift of the French state, the brutalization of social relations through its police, violence of all kinds and impunity are a major scandal," the league's president Patrick Baudouin said on Friday.
Rights groups have raised concerns over the repeated use by police of "kettling," also called "trap and detain" in the United States, a crowd-control tactic consisting of cordoning off protesters in a small area.
They have sounded the alarm after reports from recent protests of police detaining foreign schoolchildren, firing tear gas at kettled protesters, and even hurting a man so badly he had to have a testicle amputated.
Council of Europe slams 'excessive' police force
The Council of Europe – the continent's leading human rights watchdog – on Friday criticized French police's "excessive use of force" during demonstrations against the unpopular pension reform.
"Violent incidents have occurred, including some that have targeted the forces of law and order," its commissioner for human rights Dunja Mijatovic said.
"But the sporadic acts of violence of some protesters or other reprehensible acts committed by other persons during a protest cannot justify excessive use of force by agents of the state. These acts are also not enough to deprive peaceful protesters of their right to freedom of assembly," she said.
"It is up to the authorities to allow the actual exercise of these freedoms by protecting peaceful demonstrators and journalists covering these protests against police brutality and against violent individuals acting within or on the sidelines of marches," she added.
Teenagers, jogger detained
Macron's government last week used a controversial executive power to adopt the pensions bill without a parliamentary vote, sparking spontaneous protests in major cities.
In the days since, videos of police actions that appeared on social media appeared to show police knocking over or hitting demonstrators.
Human Rights Watch (HRW) told Agence France-Presse (AFP) it was very concerned about "what appears to be abusive police practices."
They echoed similar "abusive crowd control and anti-riot tactics" during the anti-government "Yellow Vest" movement in 2018-2019 during Macron's previous term in office, said the group.
"The French authorities have apparently not drawn lessons from this or reviewed their police crowd control policies and practices," HRW's France director Benedicte Jeannerod said.
Critics have denounced police carrying out sweeping "preventive" detentions, saying even blameless passersby have been caught up in their dragnet.
In one instance on Thursday night last week, two 15-year-old Austrians on a school trip were among those kettled by police, Liberation newspaper reported.
The teenagers, who had been trying to find their host families, spent the night in jail before their embassy intervened.
A man out jogging was detained the same night.
He told France Inter radio he was booked on allegations ticked at random on the charge sheet, and not released until the following afternoon.
While the security forces detained 292 people that night, 283 of them were freed without charge.
Amnesty International has raised the alarm over the "widespread use of excessive force and arbitrary arrests."
Reporters Without Borders has said police assaulted several "clearly identifiable" journalists.
'Particularly well adapted to dispersing'
Macron on Friday condemned the overnight violence and claimed security forces had worked "in an exemplary manner."
Interior Minister Gerald Darmanin said the police had responded to "troublemakers, often from the far left," who had caused 441 police to be injured.
The AFP saw suspected anarchists and other protesters setting fire to rubbish, smashing shop windows and launching stones and fireworks at security forces.
Darmanin said that 11 internal inquiries had been opened into alleged police brutality in the past week.
"It is possible that, individually, police, often because they are tired, commit acts inconsistent with what they were taught," he said defending the police brutality.
In one incident on Monday, a woman complained that a member of an infamous police motorbike unit, known as BRAV-M, hit her with a truncheon while she was caught against a wall in Paris, a source following the case told AFP.
Earlier this year, police on Jan. 19 beat a man so hard with a truncheon that he had to have a testicle amputated, his lawyer told AFP.
Paris police chief Laurent Nunez insisted earlier this week there had been no "unjustified" or "preventive" arrests. But he admitted security forces did detain people from, what they referred to as, groups formed "with a view to commit violence."
Despite the outcry, he also defended the infamous police motorbike unit, which critics have called to be disbanded, as being one "particularly well adapted to dispersing" such groups.
Right groups have long accused French police of brutality and racism, and say internal investigations seem to result in few sanctions.