The 50-year-old moonwalking former child star, who became known the world over as the King of Pop, was not breathing when paramedics arrived at his rented home in Los Angeles.
He was taken to the University of California, Los Angeles Medical Centre, where he died at 1.07 p.m. Pacific time Thursday (1.37 a.m. IST Friday).
"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," said Jackson's ex-wife Lisa Marie Presley, daughter of Elvis Presley.
At the time of his death Jackson had been preparing for a 50-concert run in London that was meant to represent his comeback and secure his financial future.
British Prime Minister Gordon Brown Friday paid tribute to Michael Jackson, saying that the singer's death was "very sad news" for his fans.
"This is very sad news for the millions of Michael Jackson fans in Britain and around the world," Brown's spokesman said.
"The prime minister's thoughts are with Michael Jackson's family at this time."
In Australia, Jackson's fans expressed their grief over his death.
Thomson Kottarathara wrote in The Age newspaper website: "Sad day for music. MJ was a legend. Love all the timeless music and the images he provided us with. MICHAEL, you will remain in our hearts. RIP."
Yann said: "The king of pop is dead, am sure anyone from the X generation will feel little bit sad, in the 80's we had the greatest concerts, their where the great days. The moon dance unh!! that was so cool. And then the 90's came thats when Michael just went coucou!!"
In Malaysia, hundreds of Michael Jackson fans jammed the phone lines of a national radio station to express their shock on learning about death of the King of Pop.
Anida Mohamad Tahrim, network programme manager with Fly FM, said the station had been flooded with calls from Jackson's fans, many in tears as they struggled to come to terms with the performer's death.
There was grief over Michael Jackson's death in China.
"When having an English name became a fashion, many, even some girls, chose Michael ... One reason was because of Michael Jordan and the other reason was Jackson," a poster using the name Summers wrote on the website of the China Daily newspaper.
A winner of 13 Grammy awards, Jackson etched a place for himself in the hearts and minds of people with his signature song and dance moves, unusual wardrobe, feminine voice - and also as Wacko Jacko for the weirdest controversies.
Jackson was born into fame Aug 29, 1958, in Gary, Indiana, US. He never knew real life. He was five, the youngest member of his family band, the Jackson 5, and was clearly the most popular. Having already established his star power at such a young age, his next foray into pop mainstream was his critically acclaimed album "Off the Wall" in 1979.
It was "Thriller" in 1982 that catapulted him into superstardom. The video for the song "Thriller" was a breakthrough success on MTV and heralded the age of the music video. It went platinum or diamond in 16 countries, including Britain, France and Japan.
But it was in 1983 that Jackson introduced a dance move that will most probably be the defining visual burnished in fans' memories - the moonwalk. That singular dance move could well be the greatest move of all time.
Throughout his career, Jackson blurred the lines between artist, icon, and sadly ridiculed celebrity. Apart from "Thriller" and "Bad", he had a string of hits in the 1980s like "Beat It" and "Man In the Mirror".
Jackson held eight Guinness records, including most successful entertainer of all time.
Things really started going bad for him in 1993. That's when the first allegations of sexual abuse by him surfaced. It was settled quietly out of court. He also scorched headlines for multiple plastic surgeries and increasingly odd behaviour.
Despite earning hundreds of millions of dollars he was reported to be $500 million in debt thanks largely to his eccentrically extravagant lifestyle.