In an interview with Senate Judiciary Committee investigators on Tuesday, Supreme Court nominee Brett Kavanaugh lit into the mounting sexual misconduct allegations against him, calling the litany of uncorroborated claims a "disgrace" that is "doing damage to the country."

Transcripts documenting Kavanaugh's sometimes-exasperated responses were released by the Judiciary Committee on Wednesday night. Democrats on the committee attended the interview but did not participate.

Kavanaugh was asked specifically about a new claim in a letter received by Sen. Cory Gardner, R-Colo., from an anonymous individual apparently in Denver, alleging that Kavanaugh "shoved" someone up against a wall "very aggressively and sexually" during an outing in front of four witnesses. Gardner's office received the letter on Sept. 22.

"We're dealing with an anonymous letter about an anonymous person and an anonymous friend," Kavanaugh said. "It's ridiculous. Total Twilight Zone. And no, I've never done anything like that."

"It's doing damage to the country. It's doing damage to this process." — Supreme Court nominee Brett Kavanaugh

He goes on to expressly deny recalling socializing with anyone from Colorado in 1998, when he was a key lawyer working for Independent Counsel Ken Starr.

He added: "I think this is -- this is crazy town. It's a smear campaign. ... It's just outrageous. It's trying to take me down, trying to take down my family.

"It's bad -- it's doing damage to the Supreme Court," he continued. "It's doing damage to the country. It's doing damage to this process. It's become a total feeding frenzy, you know? Every -- just unbelievable."

Kavanaugh, at length, described to investigators his 12 years of service on the D.C. Circuit Court of Appeals, his six FBI background investigations, tenure in the White House Counsel's office and appearances at multiple Yale reunions and panels over the past several decades.

"In all that time, not a word," Kavanaugh said. "And then 4 days, you know, when just right before a vote for the Supreme Court, after the nomination itself has been pending for months, and I've been through the hearings and 65 Senate meetings and all the written questions, and then -- and then, after all these years, with all this time, and all these descriptions with no corroboration and with her best friend saying she never heard about it, you know, I'm -- I'm really just, you know, stunned. And outraged."

The committee also released a copy of the unsigned letter. In a statement, committee spokesperson Taylor Foy told Fox News, "We have no reason to assign the letter credibility, and even if we did, we’d have no way to investigate the allegation as it was made anonymously and cannot be corroborated.

"To make sure no stone was left unturned, the committee asked Judge Kavanaugh yesterday about this anonymous letter," Foy continued. "Judge Kavanaugh flatly denied any such event ever happened."

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None of the sexual misconduct allegations against Kavanaugh has first-hand corroboration. In The New Yorker on Sunday, former Kavanaugh classmate Deborah Ramirez claimed that Kavanaugh had exposed his penis to her at a party decades ago, even as her close college friend denied ever hearing about the episode and suggested she was making the claim for political reasons.

Kavanaguh also rejected uncorroborated new claims by Julie Swetnick, who is represented by anti-Trump lawyer Michael Avenatti, that he was involved in gang rapes and systematic rape "trains" at parties in the 1980s.

"I've never participated in a gang rape," Kavanaugh said. "I've never participated in sexual activity with more than one woman present and me. I think -- yeah. Just making sure I accurately described that. In other words, I've never had a threesome or more than a threesome."

Committee investigators additionally asked Kavanaugh about a call received by Sen. Sheldon Whitehouse, D-R.I., on Tuesday, in which an anonymous constituent claimed that in 1985, two "heavily inebriated men" referred to as "Brett and Mark" had sexually assaulted a close friend of hers on a boat. The constituent apparently recanted the claim Wednesday night on Twitter.

Kavanaugh classmate Mark Judge had been identified by another accuser, Christine Blasey Ford, as participating in a separate alleged assault.

In response, Kavanuagh categorically denied the claim, saying, "I was not in Newport, haven't been on a boat in Newport. Not with Mark Judge on a boat, nor all those three things combined. This is just completely made up, or at least not me. I don't know what they're referring to."

According to the transcript, the person making the Rhode Island accusations appeared associated with a Twitter account that advocated removing President Trump from the White House by means of military coup. On Wednesday, a post on the account read, "Do everyone who is going crazy about what I had said I have recanted because I have made a mistake and apologize for such mistake."

Separately, the committee released transcripts of Kavanaugh's conversations with investigators, also under penalty of felony, from Sept. 17, when he flatly denied involvement in Ford's purported assault at a house party more than three decades ago.

None of the witnesses Ford has identified as being at the party during the alleged assault have backed up her claims, and apparent inconsistencies have emerged in her retelling of events.

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Lawyers for Ford on Wednesday released the results of a polygraph examination she took Aug. 7 -- but a key detail in the report appears to contradict Ford's past claims. The examination, which was administered by former FBI agent Jeremiah Hanafin, took place in a Hilton hotel in Maryland, according to a "Polygraph Examination Report" compiled by Hanafin.

Hanafin first allowed Ford and attorney Lisa Banks to meet alone to formulate a handwritten statement that Ford signed and provided Hanafin when he returned to the room. Then, without Banks present, Hanafin interviewed Ford about the day of the alleged assault, according to the report.

In the handwritten statement, Ford wrote that "there were 4 boys and a couple of girls" at the party.

But in Ford's letter to Sen. Dianne Feinstein, D-Calif., in July, Ford gave a different tally, writing that the gathering "included me and 4 others."

Republicans have accused Feinstein's staff of sitting on Ford's allegations for weeks and leaking the existence of the letter only days before a key vote on Kavanaugh's confirmation earlier this month, which they said compromised Ford's anonymity for their political gain.

Kavanaugh and Ford are set to testify Thursday at 10 a.m. ET before the committee. Experienced sex-crimes prosecutor Rachel Mitchell is expected to handle at least some of the questioning from Republican senators to Ford and Kavanaugh.

Fox News' Shannon Bream and Chad Pergram contributed to this report.