Chuck Berry collapses during performance

Rock 'n' roll pioneer Chuck Berry has reportedly collapsed on stage during a concert in Chicago.

According to the Chicago Sun Times, Berry was playing the keyboard when band members noticed that he had slumped onto the instrument.

The 84-year-old remained face down on the keyboard for a number of minutes until being helped off the stage.

The 'Johnny B. Goode' singer later returned to the stage, but the venue had mostly emptied by this point and he admitted to the live crowd that he was unable to continue.

Berry was inspected by a medical practitioner following the incident but signed a refusal of further treatment after insisting that he felt fine.