Avenatti claims he turned the tape over to Cook County prosecutors last weekend

A previously unknown, 45-minute-long tape allegedly featuring R. Kelly engaging in sex acts with an underage girl has been handed over to prosecutors in Chicago, lawyer Michael Avenatti said Thursday.

Avenatti told CNN that Cook County prosecutors investigating the allegations facing the embattled singer were given the tape last weekend on behalf of his client, a “whistleblower” who previously worked with the star.

The explicit video reportedly shows a man “who appears to be R. Kelly” and a girl having sex as they make mention of her “14-year-old” genitalia six different times, according to CNN.

The man also allegedly asks the girl to urinate on him, and she obliges.

Credit: Getty (2)

Avenatti, who also represents Stormy Daniels — an adult film star who has claimed she had an affair with President Donald Trump, which he denies — said in a statement that he took on “multiple” clients with connections to Kelly, 52, last April, and has been poring through documents and evidence in the months since.

“It has now resulted in the discovery of significant new evidence conclusively establishing Mr. Kelly’s illegal sexual assault of young girls,” he wrote in a statement on Twitter. “Mr. Kelly is a predator and a criminal who has prayed [sic] on young, vulnerable girls for far too long. The time has come for him to finally be held accountable for his actions.” PEOPLE has not viewed the tape, and can not independently verify its contents.

On Thursday, State’s Attorney’s Office chief communications officer Tandra R. Simonton told CNN, “We cannot confirm or deny an investigation.”

The State Attorney’s Office did not immediately respond to PEOPLE’s request for comment.

RELATED VIDEO: Lawyer for R. Kelly Denies All Sexual Abuse Allegations Against the R&B Singer

The “I Believe I Can Fly” singer’s attorney Steve Greenberg told CNN he was “unaware” of any new information regarding his client.

“We have not been contacted by anyone. We have not been informed about any new information by anyone and we have not been contacted by law enforcement,” he said.

Greenberg later replied to PEOPLE’s request for comment in a lengthy statement, reproduced here in part.

“This morning I woke up to reports that a video had surfaced showing R Kelly allegedly with an underage girl. The reports were prompted from a tweet by Michael Avenatti, who himself was the subject of unfavorable news articles just yesterday. Timing is everything,” the statement read.

“The calls and emails I received were the first I’ve heard of these allegations. I understand that CNN says that they have seen this video. If the video were what it is claimed to be, by sharing it with CNN Mr. Avenatti would be committing a felony, as would the reporter who viewed it. I doubt if either would put themselves in that position. That combined with the other facts that I know lead me to question the reports.”

Greenberg continued, “I have not been contacted by anyone connected with law enforcement, nor has R Kelly. Mr. Kelly denies that he has engaged in any illegal conduct, of any kind whatsoever. He would like to be able to continue to write and sing and produce and perform. … We will have no further comment. Thanks to all his fans and their support.”

R. Kelly
| Credit: Earl Gibson III/Getty

The actions reportedly featured in the tape echo that of a similar act featured in a sex tape allegedly showing Kelly and another underage girl that led to his 2002 arrest on child pornography charges. Six years later, a Cook County jury found Kelly not guilty on all 14 counts.

Kelly’s alleged behavior came to the media forefront again in July 2017, when BuzzFeed published a bombshell report accusing the star of running a “sex cult” out of his Chicago and Atlanta-area homes.

The star was reported to have seduced a slew of young women with the promise of helping them kickstart a music career, only to “groom” them into being his personal sex objects for whom he allegedly controlled every aspect of their lives.

Kelly has repeatedly denied all claims against him, though a renewed interest in the allegations emerged earlier this year with the release of the Lifetime documentary series Surviving R. Kelly.

The singer, whose real name is Robert Kelly, is reportedly under investigation in the state of Georgia for his alleged sex abuse, according to a January New York Times report.

In the year and a half since the BuzzFeed report, fans and famous faces have launched a #MuteRKelly campaign in the hopes of removing the star’s music from the radio and platforms like Spotify and Apple Music.

Musicians who have collaborated in the past with Kelly, like Lady Gaga and Chance the Rapper, have also condemned his alleged actions and have expressed regret over working with him.

Both Kelly’s ex-wife and his daughter have also weighed in, with ex Andrea “Drea” Kelly saying in January that he was verbally, emotionally, physically and sexually abusive.

“My heart is torn into two separate places,” 21-year-old daughter Buku Abi said on Good Morning Britain. “It’s very painful to see that all of these people are now being affected and have been affected by somebody who I do care about and have a very strenuous relationship with.”

If you suspect domestic violence, call the National Domestic Violence Hotline at 1-800-799-7233, or go to thehotline.org. All calls are toll-free and confidential. The hotline is available 24/7 in more than 170 languages.