R Kelly has been charged with 10 counts of aggravated criminal sexual abuse, at least nine of which involve minors.
The R&B star, whose real name is Robert Sylvester Kelly, has faced decades of claims of sexual abuse against women and teenagers below the age of consent.
He has never been convicted and has previously denied other allegations.
An arrest warrant was issued, and the 52-year-old turned himself in to police in Chicago later on Friday. His lawyer says he is “shell-shocked”.
Steve Greenberg told The Associated Press that his client was “extraordinarily disappointed and depressed” by the charges and maintains his innocence.
The indictment come just weeks after a documentary series called Surviving R Kelly aired.
It contained decades of allegations of abuse against R Kelly, from many women, including the singer’s ex-wife.
What are the allegations?
Prosecutors in Cook County announced the aggravated criminal sexual abuse charges, involving four victims, on Friday.
They say they took place between 1998 and 2010. Documents say at least three of the victims were aged between 13 and 16 at the time of their reported assaults.
Cook County State’s Attorney Kim Foxx said he could face a maximum of seven years in prison for each count.
A no-bail arrest warrant has been issued for Kelly.
Mr Greenberg, his lawyer, told AP that he had offered to sit down with prosecutors before the filing to describe “why these charges are baseless” but said they refused.
How did the charges come about?
Cook County State’s Attorney Kim Foxx had urged women to come forward after the documentary series aired.
Lawyer Michael Avenatti has said he is representing six people, including two alleged victims, making allegations against Kelly. At least one of the victims is included in Friday’s indictment, he said.
Mr Avenatti came forward last week to say he had uncovered and handed over previously unreleased footage showing Kelly engaging in sex with an underage girl to prosecutors.
The lawyer says the 40-minute tape, believed to be shot in 1999, shows him having sexual intercourse and engaging in other sexual and lewd acts with a 14-year-old. He has alleged both Kelly and the girl “repeatedly” reference her age as being 14 in the video.
Kelly was previously acquitted over another video tape of a similar nature in 2008.
US broadcaster CNN has said it has seen the new footage and described it as “clear and explicit”.
The charges come one day after lawyer Gloria Allred said she was representing two new women making fresh allegations against Kelly.
Decades of allegations
Kelly has faced, and denied, accusations about sexual and physical abuse for decades.
In 1994 it was reported he married 15-year-old singer and musical protégé Aaliyah at a secret ceremony in Chicago when he was 27. US media said she had lied about her age on the certificate, and the marriage was later annulled.
In 2002 the star was charged with child pornography in Chicago over footage that appeared to show him engaging in intercourse, oral sex, urination, and other sexual acts with a girl said to be 13 or 14.
The case took six years to go to trial. Both Kelly and the girl alleged to be in the video denied it was them. Eventually the jury acquitted Kelly of all 14 charges against him.
In 2017, Kelly was forced to deny allegations that he was holding a number of young women captive in a so-called “abusive cult” after a bombshell report from Buzzfeed News.
He has also been sued privately by a number of women, including some who allege underage sexual relationships and another who says he “intentionally” infected her with a sexually transmitted disease.
The singer has continued to make music throughout the allegations.
There have been calls to boycott Kelly’s music – both recordings and performances – with people using the social media hashtag #MuteRKelly.
Throughout 2018 women continued to come forward publicly alleging abuse.
The singer was the subject of the documentary series Surviving R Kelly earlier this year.
Across six episodes, a catalogue of women accused him of sexual and emotional abuse – including several who said they were underage when sexual relations began.
After the series aired, Cook County State’s Attorney Kim Foxx made a plea for victims to come forward and report – saying she was “sickened” by the allegations.