A man who said he was cleaning out an old videotape collection found what he thought was a recording of R&B singer R Kelly in concert, but instead turned out to show a man who appeared to be Kelly sexually abusing girls, he and his lawyer said on Sunday.
The man then turned the tape over to law enforcement, according to lawyer Gloria Allred.
She and her client, Gary Dennis, would not discuss the specifics of the tape during a news conference in New York.
But Ms Allred said it appeared to show an incident separate from the 10 counts of aggravated sexual abuse that Kelly faces in Chicago.
She acknowledged she could not be “100% certain” that the man in the tape is Kelly.
Steve Greenberg, a lawyer for Kelly, said: “It is not him.” He also said that Kelly “denies that he is on any tape with underaged girls”.
Mr Dennis, an assistant at a nursing home, said he was cleaning out a box of old videotapes in his home recently when he found the footage.
Mr Dennis said he has never met Kelly and does not know how the tape came to be in his possession.
He said that because the tape also has a sports game on it, he believes it may have come from a friend.
“To my shock and surprise, R Kelly appeared to be on the tape, but not in concert,” Mr Dennis said.
He said he was disgusted and horrified at what he saw.
The charges Kelly faces in Chicago are in connection with three girls and one woman.
Kelly has been dogged for decades by allegations that he victimised women and girls.
He and his lawyers repeatedly denied allegations of sexual misconduct, and he has pleaded not guilty to the charges filed last month in Chicago.
In an interview that aired Wednesday and Thursday on CBS This Morning, Kelly pleaded with viewers to believe that he never had sex with anyone under 17 and never held anyone against their will.
Ms Allred, who represents women who say they were abused by Kelly, said the tape from Mr Dennis was turned over to law enforcement in the federal Eastern District of New York.
