On the sidelines of the Labour Day protests in the French capital shortly after 4pm dozens of protesters stormed into the hospital of La Pitié-Salpêtrière in the 13th arrondissement.
“When I arrived, the gate had been forced, the chain had given way, and dozens of people were entering the hospital compound,” hospital director Marie-Anne Ruder told France Inter.
Among the “intruders”, there were yellow vests and individuals with concealed faces, she said, adding that she called the police because of their “violent and threatening actions”.
The police arrived after “ten minutes” and removed the intruders, Ruder said.
The director of Assistance Publique – Hopitaux de Paris (AP HP), the university hospital trust operating in the Paris area, Martin Hirsch told BFM TV that dozens of people “rushed up a staircase, crossing over a bridge to the surgical resuscitation unit”, which cares for “particularly vulnerable patients”.
Hirsch added that in the video surveillance images there are “nurses, a junior doctor (…) who were holding the door with all the force they could, shouting: be careful, there are patients here!”.
An investigation has been opened into the incident and about 30 people have been placed in custody, according to the Paris prosecutor's office.
Naturally the event has sparked a big reaction from France's politicians.
Interior Minister Christophe Castaner described it as an “attack by dozens of ultra-leftist anti-capitalist 'Black Bloc' activists” while France's Health Minister Agnès Buzyn said it was “unspeakable to attack a hospital”.
However it remains unclear whether the intrusion was an attack, whether the protesters were actually trying to escape the police or whether they were on the hunt for a riot police officer who had been hospitalised there after being wounded during the demonstrations.
“I do not know the reasons for this inexplicable intrusion,” said the director of the university hospital trust, Hirsch. “I do not think it has anything to do with the hospitalisation of the CRS officer – I did not see them screaming for a particular wounded person.
“I do not know if it was a hospital invasion or if they were fleeing something.
“There was no damage, thanks to the coolness of the team that held the door, and thanks to the police who intervened quickly,” he added.
On the day itself there were several videos being shared on social media showing women, men, both with and without yellow vests, displaying no visible signs of aggression, taking refuge in the grounds of the hospital close to the entrance of a building to escape the tear gas used by the police.
However at the time of writing it isn't clear whether the people using the hospital as shelter are the same ones who burst through its doors.
This isn't the first incident of its kind to take place in the French capital – back in 2016 mass demonstrations against labour reforms saw rioters vandalise the renowned Necker children's hospital in Paris.
Overview of the day's events
Although the protests did involve some violence, particularly a the beginning, they were far less disruptive than police had feared.
Riot police fired teargas as they squared off against hardline demonstrators among the tens of thousands of protesters, who flooded parts of the city in a test for France's zero-tolerance policy on street violence.
Tensions were palpable as a mix of labour unionists, “yellow vest” demonstrators and anti-capitalists gathered in the French capital, putting security forces on high alert.
More than 7,400 police were out on the streets with orders from President Emmanuel Macron to take an “extremely firm stance” if faced with violence.
The clashes kicked off as crowds gathered on Montparnasse Boulevard, with hundreds of black-clad anarchists weaving their way to the front as thousands
of unionists and yellow vests were quietly munching their lunch in the sun.
Suddenly they pounced, hurling bottles and chunks of broken paving stones at the security forces, shouting: “Everyone hates the police!”.
But the initial violence and the sporadic clashes that followed fell short of the “apocalypse” threatened by hardliners, with the security forces heading off some of the excesses seen in recent months.
Authorities had warned this year's marches would likely spell trouble, coming barely a week after leaders of the yellow vest anti-government movement angrily dismissed Macron's offer of tax cuts.
Some 40,000 people turned out for the May Day rallies in Paris, an independent media count estimated, while unions gave a figure of 80,000 and the interior ministry put the number at 28,000.
Ministry figures for the whole country gave a turnout of 164,000 people, while France's powerful CGT union gave a figure of 310,000 at events in some 250 towns and cities.
After the initial scuffles, a sense of relative calm returned as the main procession got under way.
But things degenerated again towards the end as the marchers reached Place d'Italie where black-clad agitators tried to knock down anti-riot barriers, prompting running battles with the police as the skies quickly filled with tear gas.
In the surrounding streets, some torched dustbins, while others pried the protective chipboard coverings from shop fronts and set them alight, sending black smoke pouring into the air.
The sudden violence caught many marchers by surprise, with union members who were caught in the crossfire infuriated by what they claimed was an indiscriminate police crackdown.
Caught up in the melee was top CGT official Philippe Martinez who had been waiting at the head of the march where the clashes took place.
Forced to leave the area, he later returned, visibly agitated, with sharp words of criticism for the police whom he accused of attacking “clearly-identifiable union members”.
However the police defended themselves, saying it was the 'Black Bloc' who were responsible for the violence.
“Contrary to the assertions of the general secretary of the CGT (Philippe Martinez), the many videos, taken from various angles, demonstrate the infiltration of 'Black Bloc' members right where Mr.Martinez was,” said police union Atternative on Thursday morning.