Police search Benalla's office at the Élysée presidential palace
The raid deepens the political crisis plaguing the presidential palace, which has been accused of mounting a cover-up.
Alexandre Benalla, 26, was not sacked or charged until French media broke the scandal last week, despite senior officials knowing about the May Day incident. He also reportedly enjoyed perks unusual for someone of his rank.
Benalla was given a two-week suspension days after the incident and removed from organising the president's security during his trips. But the alleged assault was not reported to prosecutors, despite a law requiring public officials to alert authorities if laws are broken.
The story only went public when Le Monde published videos of Benalla hitting one protester and wrestling with another while wearing a police helmet.
Benalla has since been charged with assault and impersonating a police officer. It has also emerged that he continued to draw a salary during his supposedly unpaid suspension.
Vincent Crase, an associate and security agent employed by Macron's La République en Marche (LREM) party who was also at the scene, has also been charged along with three police officers.
Facing political fire
France's opposition lashed out at Macron on Wednesday over his response to the revelations, accusing the president of mishandling the worst scandal he has faced since he took office.
After days of silence, Macron finally spoke out late Tuesday.
"What happened on May 1 is terrible, serious, and for me it was a disappointment and a betrayal," Macron told lawmakers from his LREM party.
"The only person responsible for this affair is me," he said.
"If they're looking for someone to hold responsible, he's right in front of you. They can come and get me."
But he also took aim at parliament's decision to grill his top aides as well as the copious press coverage of the affair.
Many politicians blasted Macron's apparent criticism of the parliamentary interrogation of his staff, with far-left MP Alexis Corbière accusing him of "swaggering" and Gerard Larcher of the right-wing Les Républicains describing the response as one of "amateurism and panic".
Lawmakers say serious unanswered questions remain about the Benalla affair, which has also come to be known as "Benallagate", and are increasingly calling for Macron to address the nation.
Socialist leader Olivier Faure said the scandal marked a turning point for the Macron presidency.
"It's the end of innocence," he said. "We can no longer look at Emmanuel Macron and his majority as if they haven't lied, betrayed and hidden the truth."
Government spokesman Benjamin Griveaux, promising "deep changes", said the administration would deal with lessons from the scandal in September after the summer break, "once it has been clearly established what went wrong".
Macron's cabinet chief, Patrick Strzoda, told lawmakers on Tuesday that he decided there were not enough elements to justify turning Benalla over to prosecutors, not least because no criminal complaint had been filed against him.
Macron's chief of staff Alexis Kohler will appear before the Senate committee on Thursday.
The scandal comes 14 months after Macron was elected vowing to restore integrity to French politics, and polls suggest the 40-year-old's poll ratings – already low – have taken a further hit.
An Ipsos poll published Tuesday found that a record 60 percent reported an unfavourable opinion of Macron.
(FRANCE 24 with AFP)
