Grammy-winning jazz saxophonist Ornette Coleman has collapsed because of heat stroke at a music festival in the United States, according to reports.
Coleman had been appearing on the last day of the festival
He was taken to hospital in Manchester, Tennessee after falling ill onstage at the Bonnaroo festival, Billboard said.
The 77-year-old received a lifetime achievement award at February's Grammys and released his first album in 1958.
He is known for collaborations with artists such as Pat Metheny and Jerry Garcia of the Grateful Dead.
He also plays the trumpet and the violin, and he and his quartet are due to embark on a European tour next month.
This will see him playing in the UK, Italy, the Netherlands, Norway, Poland and Spain.
However, it was not clear whether these concerts would be affected by his collapse.
Coleman was understood to have told medical staff that he had not felt unwell beforehand.
He was appearing on the final day of the four-day festival, a multi-genre event which had also featured artists such as The Police, the White Stripes, Franz Ferdinand and Lily Allen.