By Clotaire Achi and Antony Paone
Dozens of masked and hooded anarchists clashed with riot police in Paris, burning bins, smashing property and hurling bottles and rocks, hijacking a May Day rally that was focused on protesting against President Emmanuel Macron's policies.
Tens of thousands of labor union and "yellow vest" protesters were on the streets across France, days after Macron outlined a response to months of street protests including tax cuts worth around 5 billion euros ($NZ8.5 billion).
In Paris on Wednesday (local time), riot police used tear gas and a water cannon, and charged sporadically at several points along the traditional International Workers' Day rally to disperse groups of masked protesters who had immersed themselves in the crowd.
Some 7,400 police were deployed and they made 380 arrests. Thirty-eight people were wounded, including 14 police officers with one being hit on the head with a paving stone.
The main march crossing the southern part of the capital was finally able to move amid relative calm after being prevented from setting off by the clashes, although it appeared that yellow vests and more radical elements rather than labor unions were dominating the march.
The hard-left CGT union denounced police violence and said its secretary general had been tear-gassed.
"This current scenario, scandalous and unprecedented, is unacceptable in our democracy," it said in a statement.
The Paris police department denied excessive violence.
On the whole, compared to a year ago and some recent yellow vest protests, the violence was contained, did not spiral out of control and the protests appeared to end peacefully.
French police had warned on Tuesday that there could be clashes with far-left anarchist groups, known as Black Blocs, after calls on social media for radicals to hit the streets.
Authorities had said they expected some 2,000 Black Bloc protesters from France and across Europe to turn up on the sidelines of the rallies.
The yellow vest protests, named after motorists' high-visibility jackets, began in November over fuel tax increases but have evolved into a sometimes violent revolt against politicians and a government seen as out of touch.
Mr Macron issued a series of proposals last week in response to the protests, but many in the grassroots movement, which does not have a leadership structure, have said they do not go far enough and lack detail.
The banners in the crowd reflected the anger among some in the movement who feel abandoned by Mr Macron's economic policies.
The 41-year-old former investment banker pushed a reform blitz during the first 18 months of his presidency that impressed investors but infuriated low-paid workers, who feel he favours big business and is indifferent to their struggle to make ends meet.
"Here are the thugs," one banner read, showing Mr Macron, European Union Commission President Jean-Claude Juncker and International Monetary Fund chief Christine Lagarde.
Another targeted the president directly: "Macron, what have you done to us?"
Thousands of people also demonstrated in cities from Marseille to Bordeaux and Lyon.
Some 300 yellow vest protesters tried to storm a police station in the Alpine town of Besancon and clashes broke out in Toulouse.
The Interior Ministry said some 164,500 people had demonstrated across the country, more than in 2018, including 28,000 in Paris. The CGT said there had been 310,000 in France, including 80,000 protesters in the capital alone.
"We have been trying to fight, to make ourselves heard, for six months and nobody cares. People don't understand the movement, though it seems pretty simple: We just want to live normally," said Florence, 58, a trainer in a large company who was marching in Paris.