Singer Joni Mitchell has been taken to hospital in Los Angeles.
Mitchell's website and Twitter account reported that she was in hospital, but gave no details on her condition. It was being reported on other media that the singer was found unconscious at home.
Los Angeles fire officials say paramedics answered a 911 call in Bel Air, where Mitchell lives, and took a patient to hospital.
The 71-year-old singer-songwriter told Billboard magazine in December that she has a rare skin condition, Morgellons disease, which prevents her from performing.
Still, she released a career-spanning four-disc box set last year and appeared at Clive Davis' annual pre-Grammy party in February.
Mitchell has received eight Grammy Awards, including a lifetime achievement award in 2002. She was inducted into the Rock and Roll Hall of Fame in 1997.