French authorities are investigating riot police over three incidents of alleged violence towards May Day protesters in Paris.
Videos taken during clashes between police and protesters has been circulating on social media.
One appears to show an officer insert a truncheon into a protester’s trousers on the Boulevard du Montparnasse.
In another an officer is seen slapping a protester while a third shows an officer hurling a paving stone.
Inspectors are investigating each incident at the request of Paris police chief Didier Lallement, reports say.
Interior minister Christophe Castaner said “there will be punishment” if any officers are found to be at fault.
He has himself faced calls to resign, after critics said he had spread “fake news” in accusing protesters of an “attack” on La Pitié-Salpêtrière hospital in Paris.
What the videos show
The videos were filmed as riot police were faced with May Day protests on Wednesday that involved gilets jaunes (yellow-vest) protesters and far-left “black-block” militants as well as traditional union marchers.
Journalist David Dufresne, who has highlighted allegations of police violence since the gilets jaunes protests began last year, posted the footage on his Twitter feed.
In one video, filmed on the Boulevard du Montparnasse, a protester is surrounded on the ground by CRS riot police and one appears to insert his truncheon inside the back of his trousers.
In another incident, a man is slapped twice in the face by an officer while a woman with him his pushed around.
Why is minister under pressure?
When Mr Castaner accused protesters on Thursday of attacking the hospital, hospital managers also spoke of staff having to block protesters at the door of the Pitié-Salpêtrière intensive care unit.
The large teaching hospital is in the 13th arrondissement (district) in central Paris, near Place d’Italie, where police used tear gas to disperse demonstrators on Wednesday.
The minister said on Thursday that “black block” anti-capitalist militants were responsible for an “attack” on the hospital, where Princess Diana died in 1997.
On Friday, Mr Castaner accepted he “should not have used the term” attack but maintained that protesters did enter the hospital, and instead called it a “violent intrusion”.
“I have no problem recognising that I misspoke,” he told reporters.
Edouard Philippe told reporters he had “confidence” in Mr Castaner, saying he was “right” to correct his initial statement.
What really happened at the hospital?
Hospital director Marie-Anne Ruder told French media on Thursday that protesters – including some with masks and some gilets jaunes – were “violent and threatening” when they entered the hospital’s grounds.
Videos show protesters rushing through the gate closely followed by police. Some climb the outdoor staircase towards the intensive care unit amid an atmosphere of panic, as nurses shout “this is intensive care”.
“It was more like they were fleeing something,” said nurse Mikael Matos, who insisted none of the protesters wore a mask.
“We didn’t feel attacked or in danger,” Gwenaëlle Bellocq told Le Figaro, adding that while their arrival came as a surprise, the group listened to the medical team very quickly.
Police arrested 32 people, all of whom have now been released while investigations continue.
Traditionally a union-led day of action in France, the 1 May event was marked by clashes in which protesters smashed shop windows and threw projectiles at the more than 7,000 officers deployed in Paris.
They echoed the weekly “yellow-vests” protests that have swept France since last November, shaking the government of French President Emmanuel Macron.