Jeffrey Epstein's Assistant Accuses Former Miami Beach Mayor of Sexual Assault

Jeffrey Epstein's longtime employee has accused the former mayor of Miami Beach of sexual assault ... according to a new report.

The Miami Herald reports Sarah Kellen -- Epstein's personal assistant for many years -- allegedly told the House Oversight Committee that ex-mayor Philip Levine, fashion photographer Patrick Demarchelier, and hairstylist Frédéric Fekkai sexually assaulted her.

The Herald cites multiple anonymous people who were in the committee hearing during Kellen's testimony.

Kellen did not go into detail about the alleged sexual assaults, the Herald reports ... and, though she was not sworn in, it is a crime to lie to Congress regardless.

A rep for Fekkai tells TMZ ... “That is categorically false. Mr. Fekkai never assaulted anyone. Mr. Fekkai was astonished to read of Ms. Kellen’s testimony. Mr. Fekkai never abused anyone. He never participated in any illegal behavior. He knew nothing about Epstein’s repugnant depravity or trafficking. He did nothing wrong.”

Rep. James Comer -- Chairman of the House Oversight Committee -- called Kellen "a very good, sincere and helpful witness" during a break in testimony Thursday.

Kellen reportedly told Congress that Epstein made it clear to her that defiance would get her killed ... and claimed he showed her he was more powerful than anyone else in the world.

She allegedly name-dropped other well-known figures she met while traveling with Epstein ... from Fidel Castro and Princess Beatrice to Bill Clinton and Ehud Barak.

Kellen said, "Jeffrey was able to fool and manipulate the brightest minds in the world. Us victims didn’t stand a chance.”

Former Mayor Levine previously denied any relationship with Epstein ... but emails that have surfaced in the last few years seemingly show multiple communications between the pair.