R&B singer R. Kelly has pleaded not guilty to 13 sexual abuse charges in Chicago, including allegations involving a new accuser.

The new alleged victim, referred to as Minor Six, was included as part of an updated federal accusation.

Prosecutors also said they had seized more than 100 electronic devices, such as smartphones, iPads and hard drives, after carrying out a search warrant.

The judge set a trial date for 13 October, six months later than planned.

The case includes several charges accusing Kelly of child pornography but the accused has consistently denied the allegations.

The updated indictment is largely the same as the original, which also had 13 charges, but now includes a reference to Minor Six.

Prosecutors offered little detail about the new alleged victim, but said the person met Kelly in the late 1990s at the age of 14 or 15.

The indictment said Kelly “engaged in sexual contact and sexual acts” with Minor Six and four others when they were aged under 18.