A senior French presidential aide is to be dismissed from his job, officials say, after footage emerged of protesters in Paris being attacked by a man wearing a police visor.
The action against Alexandre Benalla was taken after "new facts" emerged in the case, French President Emmanuel Macron's office said on Friday.
Mr Benalla is being questioned over the footage of the May Day protests.
There were calls for him to be sacked after he was identified in a newspaper.
Police are questioning Mr Benalla, an assistant to Mr Macron's chief of staff, over footage filmed by a student activist showing a woman and a man being beaten during the demonstrations on 1 May.
French newspaper Le Monde identified the attacker as Mr Benalla.
While he faces questions over the assault, prosecutors said on Friday that he is also facing charges of impersonating a police officer.
In May, a few days after the incident, Mr Benalla was given a two-week suspension, but nothing was reported to prosecutors. The BBC's Hugh Schofield in Paris says that this suggests that Mr Macron's office may have already been aware of his actions.
A source close to the inquiry said that three police officers had also been suspended on suspicion of providing Mr Benalla with surveillance footage of the demonstration in an attempt to prove his innocence, Le Monde reports.