The world is currently in a state of shock as one of the most iconic musicians of the past 100 years has passed away.

Paramedics were called to the Michael Jackson's home around midday US time on Thursday after he stopped breathing and suffered a cardiac arrest. He was rushed to a local medical centre, but his death was announced shortly afterwards.

The singer's death is already being compared to that of Princess Diana's and has captured the same measure of shock from a global audience who stared in disbelief at their TV and computer screens.

Tributes have poured in for the 50-year-old, who will go down in history as the king of pop. 

Close friend Uri Geller was one of the first to speak of Michael's death: "I'm absolutely devastated and shocked... I really have no words. I pray that his soul is up there now. It's too surreal for me to absorb that Michael is no longer with us."

Jackson's ex-wife Lisa Marie Presley said: "I am so very sad and confused with every emotion possible. I am heartbroken for his children, who I know were everything to him and for his family. This is such a massive loss on so many levels, words fail me."

Music producer Quincy Jones told MSNBC: "I am absolutely devastated at this tragic and unexpected news." He said Jackson "had it all - talent, grace, professionalism and dedication. I've lost my little brother today, and part of my soul has gone with him."

Former bodyguard Matt Fiddes commented: "He's the most misunderstood man in world. Everyone thought he was this weird freak but when you're with him he's as normal as everyone else. I don't think he felt he was as famous as everyone else thought, he didn't know any different.

"He was a very caring guy who would go out of his way to help the sick. One night in London he wanted to see some homeless people. He sent them loads of pizzas in secret. The guy had a good heart.

"We used to dress him up and sneak out of hotel room and do normal things in shops, people wouldn't know who he was but we wanted to give him a taste of the real life."

Britney Spears, who is currently on tour with her Circus trek, paid tribute by saying: "I was so excited to see his show in London. We were going to be on tour in Europe at the same time and I was going to fly in to see him. He has been an inspiration throughout my entire life and I'm devastated he's gone!"

Justin Timberlake added that the world has not only lost one of music's most beloved stars, but has also "lost a genius".

"I can't find the words right now to express how deeply saddened I am by Michael's passing. We have lost a genius and a true ambassador of not only pop music, but of all music.

"He has been an inspiration to multiple generations and I will always cherish the moments I shared with him on stage and all of the things I learned about music from him and the time we spent together. My heart goes out to his family and loved ones."

Madonna said: "I can't stop crying over the sad news. I've always admired Michael Jackson - the world has lost one of its greats but his music will live on forever."

Ashton Kutcher wrote on his Twitter account: "RIP. Sending love and light to family and friend but especially his kids. Plea to the press to respect his wishes of maintaining the anonymity of his children. I plea to the public to refuse to consume media that does not respect the anonymity of Michaels children."

P Diddy had this to say: ""Michael Jackson showed me that you can actually see the beat. He made the music come to life! He made me believe in magic. I will miss him!"

A spokeswoman for The Outside Organisation, which was organising the publicity for the shows, said she had no comment at this time.

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