May 1 Labor Day parade on Sunday turned violent in Paris as demonstrators went on a rampage vandalizing commercial and financial establishments and clashing with public authorities, partly to protest the pension reforms of newly re-elected President Emmanuel Macron.

“The thugs come to disrupt the May Day demonstrations, particularly in Paris, by committing unacceptable violence,” Interior Minister Gerald Darmanin denounced on Twitter.

The minister also told BFMTV news that eight police personnel were injured in the clashes and 45 people were arrested, including a female protester who attacked firefighters.

The main parade was organized by trade unions and student associations to demand better working conditions and higher wages, and to oppose the proposed pension reform by Macron that would increase the retirement age from 62 to 65.

The General Confederation of Labour (CGT), one of the main organizers of the rally, claimed that 50,000 demonstrators mobilized in the march that began around 2.30 p.m. local time (1230GMT) from Place de la Republique.

A group of demonstrators wearing head-to-toe black clothes broke away from the main procession at Boulevard Voltaire and began vandalizing commercial properties, breaking glass windows of shops, and lighting fires.

The vandalism turned violent at several places as demonstrators clashed, threw projectiles at the security personnel, and riot-geared police fired tear gas shells to disrupt the crowd.

A BFMTV news report identified the destruction of around 20 properties and shops, including McDonald's, an insurance company, real estate agencies, and banks.

A video on social media showed a protester that was later identified as a woman, wearing an orange helmet clashing with the firefighters who intervened to douse a fire at the intersection of Rue Alexandre Dumas and Boulevard Voltaire.

The fire brigade, Paris Pompiers, strongly condemned the aggression towards its personnel as a “scandalous attack.”

“Shame on the savagery, this new aggression towards the firefighters of Paris in the exercise of their functions, to protect the people, the property of the City and the smooth running of the event is incomprehensible,” it said on Twitter.

Left-wing leader Jean Luc Melenchon of the Jean Luc Melenchon party, who polled in third place in the recently concluded presidential elections, said he was fed up with “parasitic violence” on May 1, which made “the march of the unions invisible and serves as propaganda for our worst adversaries.”

He blamed the Paris police for not taking timely action against the disruptors and failing to guarantee the “right to demonstrate in peace” to the aggrieved workers.

Across France, some 250 other May Day rallies were relatively peaceful.

According to CGT, 210,000 protesters turned out for the demonstrations while the Interior Ministry put the figure at 116,500.

Protesters opposed Macron's re-election, called for political change with a left-wing and socialist agenda government, and demanded a dignified retirement age of 60.