NEW YORK, July 12 — Grammy Award-winning singer R. Kelly, who faces state sexual assault charges in Illinois, was indicted today on federal charges for alleged racketeering and sex trafficking that prosecutors said occurred over the past 20 years.

Prosecutors alleged that Kelly engaged in a scheme to recruit women and girls to engage in illegal sexual activity, in a five-count federal indictment that was unsealed in US District Court in New York’s Brooklyn borough today.

Kelly, who was arrested yesterday evening in Chicago, also faces a 13-count federal indictment on sex crime charges in that city that has yet to be unsealed, his lawyer and a law enforcement source said.

The allegations refer to conduct that stretches back to 1999, according to the indictment.

Kelly’s attorney, Steve Greenberg, said the federal charges appear to be "largely the same” as state sex assault charges Kelly currently faces and child pornography charges for which he was acquitted in 2008.

"Most, if not all of the conduct alleged, is decades old,” Greenberg wrote in a statement posted on Twitter.

Kelly, 52, an R&B singer, was arrested as he was walking his dog last night by New York police detectives and Department of Homeland Security investigators, Greenberg and the law enforcement source said. He is expected to appear before a judge in Chicago later today, the source said.

"He’s expected to be arraigned today in federal court in Chicago and at a later date in Brooklyn,” the source added.

Last month, the singer pleaded not guilty to 11 new felony counts of sexual assault and abuse at a Cook County, Illinois, court hearing, after state prosecutors expanded an indictment against him.

The R&B singer, who Greenberg said was aware of the federal investigation, has vehemently denied abuse allegations for decades.

"He and his lawyers look forward to his day in court, to the truth coming out and to his vindication from what has been an unprecedented assault by others for their own personal gain,” Greenberg said.

The Cook County charges involve alleged abuse of a victim between the ages of 13 and 16. The accusations center on someone identified only as J.P. and the crimes are alleged to have taken place between May 2009 and January 2010.

Kelly could face up to 30 years in prison if convicted on those charges.

In February, Kelly pleaded not guilty to charges that he sexually assaulted three teenage girls and a fourth woman.

The charges were brought after seven women, including his former wife, appeared on a Lifetime television documentary and accused him of emotional and sexual abuse.

The singer, known for such hits as I Believe I Can Fly and Bump N’ Grind, spent a weekend in jail on the sex charges before being released on US$100,000 bail on Feb. 25. — Reuters