[Photo by: Late Night With Seth Meyers/YouTube]

Beastie Boys' Ad-Rock, a.k.a. Adam Horovitz, is responding to sexual assault allegations made against his father, playwright and mentor Israel Horovitz.

On Thursday, nine women came forward with accounts of abuse by the elder Horovtiz in a detailed exposé for The New York Times. The women attest to a decades-long pattern of sexual misconduct, harassment and assault perpetrated by the 78-year-old co-founder of Gloucester Stage Company.

One of the women who spoke to the Times, Jocelyn Meinhardt, was Ad-Rock's high-school girlfriend. She alleges that Israel Horovitz raped her in 1989, when she was 19, during a summer fellowship with the theater company.

"I believe the allegations against my father are true," Ad-Rock makes clear in a statement, "and I stand behind the women that made them."

The women were driven to make their stories heard after the recent discoveries concerning Louis C.K., Harvey Weinstein and others. Israel Horovitz's alleged behavior was apparently not a secret to the Gloucester Stage Company—the Boston Phoenix reported their knowledge of the purported acts in 1993.

Israel Horovitz says that while he has a "different memory of some of these events, I apologize with all my heart to any woman who has ever felt compromised by my actions, and to my family and friends who have put their trust in me. To hear that I have caused pain is profoundly upsetting, as is the idea that I might have crossed a line with anyone who considered me a mentor."

Gloucester Stage Company cut ties with Horovitz upon learning of the accusations. "We are individually and collectively appalled by the allegations, both old and new," says Elizabeth Neumeier, the board's president.