Pop star Michael Jackson has died in Los Angeles, aged 50, reports say.
Paramedics were called to the singer's home around midday local time on Thursday after he stopped breathing and suffered a suspected cardiac arrest.
He was rushed by ambulance to a local medical centre, but his death was announced shortly afterwards.
The star, who had a history of health problems, had been due to begin a series of comeback concerts in the UK on 13 July. Jackson had a history of health problems and had not completed a concert tour in 12 years.
Concerns were raised last month when four of his "comeback" concerts were postponed, but organisers insisted the dates had been moved due to the complexity of staging the show. A spokeswoman for The Outside Organisation, which was organising the publicity for the shows, said she had no comment at this time.
Uri Gellar, a close friend of the star, told BBC News: "I'm devastated - it's very, very sad.
"I'm still trying to hold on to the glimmer that it's not true. It's too surreal for me to absorb that Michael is no longer with us."
US media reports said paramedics were called to the singer's house in Bel Air at midday.
They performed CPR on Jackson and rushed him to the UCLA medical centre. Crowds have begun to gather outside the facility, whose emergency centre has been roped off by police.
Jackson began his career as a child in family group The Jackson 5. He then went on to achieve global fame as a solo artist with smash hits such as "Thriller" and "Bad".
But the singer has been dogged by controversy and money trouble in recent years, becoming a virtual recluse.
He had three children, Michael Joseph Jackson Jr, Paris Michael Katherine Jackson and Prince Michael Jackson II.
BBC NEWS | Entertainment | Singer Michael Jackson dies in LA
Pop King Jackson Dies at 50
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