Scores of hooded anarchists launched projectiles at riot police, smashed up shop fronts, torched cars and burned barricades during a demonstration in the French capital on Saturday against police violence and a draft security law.
The police fired back volleys of tear gas and made repeated charges at groups of troublemakers for close to three hours. One group of anarchists ransacked the branch office of a bank, throwing piles of paperwork onto a fire outside.
It marked the second consecutive of weekend of unrest in Paris, provoked by recent episodes of police brutality and President Emmanuel Macron's security plans, which the demonstrators say would restrict civil liberties.
Rallies also took place in Marseille, Lyon, Lille and other French cities.
Thousands of people had began marching peacefully in Paris, waving banners that read "France, land of police rights" and "Withdrawal of the security law", when the clashes erupted between police and 'Black Bloc' anarchists.
Paris police said that some 500 "casseurs" - which translates as hoodlums or rioters - had infiltrated the protest, according to BFM TV. Thirty arrests had been made by 1700 GMT, the force added.
France has been hit by a wave of street protests after the government introduced a security bill in parliament that set out to increase its surveillance tools and restrict rights on circulating images of police officers in the media and online.
The bill was part of Macron's drive to get tougher on law and order ahead of elections in 2022. His government also said the police needed to be better protected from online hate.
But the draft legislation provoked a public backlash.
The beating of a Black man, music producer Michel Zecler, by several police officers in late November intensified anger. That incident came to light after closed circuit television and mobile phone footage circulated online.
In a U-turn earlier this week, Macron's ruling party said it would rewrite the article that curbs rights to circulate images of police officers. But many opponents say that is not enough.
"We're heading towards an increasingly significant limitation of freedoms. There is no justification," said Paris resident Karine Shebabo.
Another protester, Xavier Molenat, said: "France has this habit of curbing freedoms while preaching their importance to others."
Macron acknowledged on Friday that people of colour were more likely to be stopped by police for ID checks than whites. He said an online platform would be created for citizens to log unwarranted searches.
The president's remarks drew a furious response from police unions on Saturday. Alliance Police called Macron's comments shameful and denied the force was racist. The Alternative Police union threatened to halt random checks.