Singer Joni Mitchell is in intensive care in hospital and fans have been asked to "light a candle" for her.

A statement on her official website, JoniMitchell.com, said: "Joni was found unconscious in her home this afternoon. She regained consciousness on the ambulance ride to an LA area hospital.

"She is currently in intensive care undergoing tests and is awake and in good spirits. More updates to come as we hear them. Light a candle and sing a song, let's all send good wishes her way."

The first update on the 71-year-old singer's Twitter account read: "Joni has been hospitalised. We are awaiting official word on her condition and will post it here as soon as we know."

Three hours later, another post said: "Joni is currently in intensive care in an LA area hospital but is awake and in good spirits. More updates to come as we hear them."

Celebrities wished her well, including Billy Idol, who wrote: "Sorry to hear today's news about Joni Mitchell. I sang on her Dancing Clown single many moons ago, all the best for her recovery."

The Canadian-born singer is famous for hits such as Big Yellow Taxi, and has won eight Grammys in her career.