PARIS (Reuters) - Workmen cleared away burned hulks of cars, scrubbed the defaced Arc de Triomphe monument and replaced the shattered windows of luxury boutiques in Paris on Sunday after the worst riots in the center of the capital in half a century.

Vandalized cars are seen on Avenue Foch the morning after clashes with protesters wearing yellow vests, a symbol of a French drivers' protest against higher diesel taxes, in Paris, France, December 2, 2018. REUTERS/Benoit Tessier

Several thousand riot police were overwhelmed on Saturday as they fought running battles with protesters in the shadows of some of Paris’ fabled landmarks and through its fanciest shopping districts. More than 400 people were arrested and more than 100 injured, shocking Parisians and tourists alike.

At the base of the 19th-century Arc de Triomphe, police kept the public back as cleanup crews set about erasing graffiti, much of it targeting President Emmanuel Macron and some exuding anarchist sentiment such as, “Overthrow the bourgeoisie!”

“I’ve worked on monuments around Paris for 20 years and I’ve never seen anything like this at the Arc de Triomphe. It was carnage,” a Paris City Hall official overseeing the cleanup said as his team worked on a graffito reading “Macron resign”.

Lasting damage might be caused if crews are forced to erode the arch’s stonework to render it clean, he said.

Authorities were caught off-guard by the escalation in violence after two weeks of nationwide unrest against fuel taxes and high living costs, known as the “yellow vest” movement after the fluorescent jackets worn by the protesters.

On the Rue Royale in the heart of Paris, half a dozen laborers gingerly replaced glass panes on the front of a Dior store. Next door, a Chanel employee vacuumed shards of glass from the floor, while carpenters removed the plywood panels that had been protecting a Gucci shop.

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The government said it would consider a state of emergency in the face of unrest across the country.

The violence in Paris was the worst in the elegant center of the capital since the May 1968 student uprising that brought France to its knees.

“MAYBE THE ARMY SHOULD INTERVENE”

“We’re already afraid of what’s going to happen next week. The violence is escalating at an exponential rate,” said Claude, a well-heeled woman who lives next to the Belle Armee brasserie that was set ablaze. “The state is losing control. They cannot let this happen. Maybe the army should intervene.”

Parisians and tourists surveyed the aftermath, capturing the moment on smartphones as the capital digested the chaos that now poses a serious challenge to Macron’s presidency.

“Macron has a problem on his hands. Everyone’s fed up. He’s got to listen more,” said Amaya Fuster, eyeing graffiti daubed on a Printemps department store window that read: “There’s enough money in the coffers of businessmen. Share the riches!”

Authorities said violent groups from the far right and far left as well as “thugs” from the suburbs had infiltrated the yellow vests movement in Paris on Saturday.

There were signs that some of the hardcore troublemakers were part of the anarchist and anti-capitalist movement: banks, insurance companies, upmarket private homes and cafes and glitzy boutiques were among the properties smashed up and looted.

The protests are taking a toll on the economy. On Saturday, boulevards that should have been packed with tourists and Christmas shoppers resembled battle zones, as smoke and tear gas hung in the air and debris littered the ground. Hotels and department stores in the capital stand to lose millions.

“We thought, ‘Oh, that’s our holiday over’,” said Yao Lei, a Chinese tourist from Shanghai who arrived in Paris at dawn and had received video images of the chaos on his flight.

“We’re here to shop but we wondered if we’d have to go straight to Milan instead.”