Dozens of motorbikes and cars have been set on fire in eastern Paris as a yellow vest protest descended into violence.
Riot police fired tear gas to try to disperse the protesters around the Place de la Republique, but demonstrators responded by starting fires and throwing flares and paving stones.
Boarded up shops in the area were attacked by some radical protesters, and police repeatedly charged as they tried to contain the crowd.
Several thousand people had marched to the square from France's Finance Ministry.
French television showed images of volunteer medics treating a yellow-vested protester lying on the ground, with the smell of tear gas mixed with black smoke choking the air.
Witnesses reported seeing at least two journalists injured in the melee.
The Paris police headquarters said authorities had detained 126 people by early afternoon.
More than 11,000 people were earlier subjected to spot checks while trying to enter the capital for the protests.
Multiple protests were being held around Paris and other French cities on Saturday for the 23rd weekend of the yellow vest movement against wealth inequality and President Emmanuel Macron's leadership.
Protesters have also voiced frustration that the effort to save fire-damaged Notre Dame Cathedral is eclipsing the yellow vest movement's demands.
Many protesters were deeply saddened by the fire at the national monument.
But at the same time they are angry at the one billion US dollars (£770 million) in Notre Dame donations that poured in from tycoons while their own demands remain largely unmet and they struggle to make ends meet.
Mr Macron had been scheduled to lay out his responses to yellow vest concerns on Monday night - but cancelled the speech because the fire broke out.
He is now expected to do so next Thursday.
Yellow vest critics accuse Mr Macron of trying to exploit the fire for political gain - one group marching on Saturday even accused Mr Macon of "burning down Notre Dame".