Stormy Daniels' lawyer, Michael Avenatti, claims he is aware of "significant evidence" that embattled Supreme Court nominee Brett Kavanaugh was involved in "gang rapes" during his high school years

Stormy Daniels‘ lawyer, Michael Avenatti, claims he is aware of “significant evidence” that embattled Supreme Court nominee Brett Kavanaugh was involved in “gang rapes” during his high school years.

Avenatti tweeted a screenshot Sunday night of an email he wrote to Mike Davis — the chief counsel for nominations for the Senate Judiciary Committee — alleging that Kavanaugh, his friend Mark Judge, and others targeted women with drugs and alcohol “in order to allow a ‘train’ of men to subsequently gang rape them” at house parties in the early 1980s. In the letter, he did not specifically allege that Kavanaugh himself assaulted anyone.

Avenatti did not present any evidence or further details about the allegations, but said he was aware of “multiple women” who “will corroborate these facts.”

Avenatti, 47, also revealed Sunday night that he’s representing a third woman who has accused Kavanaugh, 53, of sexual assault. The attorney said he and his client will “be demanding the opportunity to present testimony” to the Senate Judiciary Committee.

“The nomination must be withdrawn,” Avenatti added.

The White House did not immediately respond to PEOPLE’s request for comment.

Avenatti later told Politico that he’s representing a group of people who can corroborate allegations involving Kavanaugh and Judge. Avenatti described one of the people as a victim and the others as witnesses.

Earlier on Sunday evening, The New Yorker reported on allegations by Deborah Ramirez, a woman who attended Yale with Kavanaugh and claims he “exposed himself at a drunken dormitory party, thrust his penis in her face, and caused her to touch it without her consent as she pushed him away.”

Kavanaugh released a statement Sunday in response to Ramirez’s allegations, saying, “This alleged event from 35 years ago did not happen. The people who knewayme then know that this did not happen, and have said so. This is a smear, plain and simple. I look forward to testifying on Thursday about the truth, and defending my good name — and the reputation for character and integrity I have spent a lifetime building — against these last-minute allegations.”

Avenatti has clarified that his client is not Ramirez, and noted that the third accuser has previously worked within the State Department, the U.S. Mint and the Department of Justice and has been granted multiple high security clearances.

“The GOP and others better be very careful in trying to suggest that she is not credible,” he said.

Later this week, Christine Blasey Ford, the first woman who accused Kavanaugh of sexual assault, is set to testify about the allegation in open court. Ford has alleged that Kavanaugh sexually assaulted her at a party while they were in high school. She claims his friend Judge was in the room at the time.

Kavanaugh has denied Ford’s allegations.

The Sentinel reported Monday that investigators in Montgomery County, Maryland, are looking into a fourth allegation of sexual assault involving Kavanaugh.

But Montgomery County police have disputed The Sentinel’s report, telling the Washington Examiner that police are not looking into any new allegations.

“I have spoken with my chief of detectives, and neither of us have any knowledge of anyone coming forward to us to report any allegations involving Judge Kavanaugh,” said police chief J. Thomas Manger.

If you or someone you care about is affected by sexual violence, contact the National Sexual Assault Hotline: 1-800-656-HOPE (4673).