Court documents charging R&B star R. Kelly with sexual abuse say the assaults occurred over a more than two-decade timeframe. Friday's charges come following the allegations made by two women Thursday, saying Kelly had sex with an underage teenager without her consent.

Charges filed Friday in Cook County Circuit Court in Chicago say the abuse dated as far back as 1998, and as recently as 2010. He is accused of sexually abusing four different victims. 

Kelly has faced allegations of sexual misconduct and abuse for decades, and was acquitted in 2008 on child pornography charges. Kelly, through his attorneys, has consistently denied the allegations. 

The allegations were spotlighted again this year in a Lifetime documentary titled "Surviving R. Kelly." Cook County State's Attorney Kim Foxx later urged victims and witnesses to come forward. 

Foxx is expected to discuss the latest charges at a Friday news conference. Kelly faces 10 counts of aggravated criminal sexual abuse.

A Chicago judge previously authorized a no-bail arrest warrant for Kelly, after the 10 counts of aggravated sexual abuse charge.

Judge Dennis Porter signed the order. No-bail arrest warrants do not necessarily mean the defendant will not eventually be offered bail, once appearing in court to answer the charges.

Kelly, whose legal name is Robert Kelly, is one of the top-selling recording artists of all time. He has won multiple Grammys, including for his hit-song, "I Believe I Can Fly.''