After being accused by a second woman of taking part in a trafficking scheme in which she was directed to have sex with him, retired Harvard Law professor Alan Dershowitz is threatening to sue.

In a tweet posted on Sunday, the legal giant warned that he would take action against the women whom he claimed were spreading lies:

I challenge my false accusers to stop hiding behind the litigation privilege and accuse me in public so I can sue them and prove they are lying for money. — Alan Dershowitz (@AlanDersh) December 23, 2018

In November, a Miami Herald investigation alleged that Dershowitz was involved in a sex slave ring led by financier and convicted pedophile Jeffrey Epstein. The newspaper cited an affidavit by Virginia Roberts, who claimed to have been lured into the operation in 2015 at age 16, and pushed by Epstein to have sex with Dershowitz.

Last week, the New York Daily News reported that another woman, Sarah Ransome, also claimed to have been directed to have sex with Dershowitz from 2006 to 2007 when she was in her 20s.

Dershowitz has defended himself against the accusations and recently penned an op-ed for the Daily News in which he contended corroboration of Ransome’s story was nonexistent.

“I never met this woman,” he wrote. “I never had sex with her. I challenge her to provide the sex tapes she claims she has and other evidence that she and her lawyers have sealed that would conclusively prove my innocence.”

Correction: The headline and text of this article have been updated to clarify that Virginia Roberts, Dershowitz’s first accuser, is the only one who claimed to have had sex with him. Sarah Ransome, his second accuser, claims to have been directed to have sex with Dershowitz, but it is unclear whether the act actually occurred.