Michael Jackson died after suffering a suspected heart attack, his brother said today.

Jermaine Jackson said he believed the 50-year-old singer suffered a cardiac arrest at his Holmby Hills home in Los Angeles yesterday and was taken to the UCLA medical centre where he was pronounced dead at 2.26pm Pacific time (10.26pm BST).

The self-style king of pop was due to perform 50 farewell concerts in London this summer, bowing out on an illustrious music career spanning several decades while aiming to resurrect his fortunes.

Jackson’s brother told reporters: “My brother, the legendary King of Pop, passed away on Thursday June 25 at 2.26pm.

“We believe he suffered a cardiac arrest at his home, however the cause of his death is unknown until the results of the autopsy are known. The personal physician who was with him at the time attempted to resuscitated him.”

A spokesman for the Ronald Reagan UCLA medical centre added: “When he arrived at hospital at approximately 1.14pm a team of doctors including emergency physicians and cardiologists attempted to resuscitate him for a period of more than one hour, they were unsuccessful.”

TV footage showed a rescue helicopter flying the star’s body to a waiting ambulance.

A Los Angeles Police Department spokesman said the robbery and homicide team was investigating Jackson’s death because of its “high profile” but warned reporters not to read anything into his team’s involvement.

A post mortem examination is expected to take place later today, Los Angeles Coroner’s Office spokesman Fred Corral said.

As tributes flooded in, close friend Uri Geller told the Press Association that it may have been the “stress” of Jackson’s London comeback that killed him.

Speaking from his home in Sonning, Berkshire, he said: “I guess the stress, the anticipation and the passion he was emitting from his heart, wanting to do this comeback so badly, maybe that got to him.

“That is all I can think, that maybe the stress killed him.”

He described Jackson, who was best man when Geller renewed his wedding vows, as a “genius”.

He said: “I’m shocked and devastated. I am hoping this is a dream I will wake up from, but it is not. Michael is dead.

“For him not to be around, that he’s gone, is just surreal. It cannot sink into my psyche. He was a genius.

“I had my rows and up and downs with him because we were friends. I voiced my opinion about what he was doing wrong and found myself shouting at him at certain times, but when this person you were so close to is taken away, is gone, it’s just unbelievable.”

Fears were sparked for Jackson’s health last month when four of his This Is It concert dates were pushed back, but organisers insisted the dates were moved due to the sheer magnitude of the spectacle.

Randy Phillips, president and chief executive officer of AEG Live, said the date changes had “absolutely nothing to do with (Jackson’s) health”.

The Rev Al Sharpton, a leading US civil rights campaigner and friend of Jackson for 35 years, said the star was a “trailblazer” and an “historic figure”.

“Michael Jackson made culture accept a person of colour way before Tiger Woods, way before Oprah Winfrey, way before Barack Obama,” he said.

“Michael did with music what they did in sports, in politics, and in television.

“No controversy will erase the historic impact.

“Michael Jackson was a trailblazer, to say an icon would only give these young people in Harlem a fraction of what he was.

“He was a historic figure that people will measure music and the industry by.”

He went on: “If he had shortcomings, they didn’t equal his strengths. And if he brought days that we all hoped were days that would never come again, they didn’t measure up to the many days, the more days, that he gave us of joy and pleasure.”

A spokeswoman for The Outside Organisation, which was organising the publicity for Jackson’s 50 farewell concerts, said she had no comment at this time.

Jackson last toured 12 years ago when he played 82 shows in 58 cities for the HIStory tour.

At the World Music Awards in London in November 2006 he performed just a few lines from We Are The World.

Matt Blank from the Michael Jackson World Network fan club told BBC News 24 he was “a bit dumbfounded and a bit shellshocked by it all”.

He added: “I find it hard to believe this could be a reality.

“In the past, health issues of Michael Jackson have always been rumoured. I can only imagine this is down to the amount of stress he was under to come out and perform.”

He added: “It’s just unimaginable that Michael Jackson is no more, it’s just unbelievable.”

He spent time living outside the United States since his 2005 acquittal on child molestation charges.

Jackson leaves three children, Michael Joseph Jackson Junior, Paris Michael Katherine Jackson and Prince “Blanket” Michael Jackson II.

Links to ticket sales were taken off the official Jackson website in the early hours of this morning, leaving a simple image of the star with the words: ``King of Pop'' and ``Michael Jackson''.

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