Jackson dies aged 50 on the eve of his 'final tour'

Huge crowds gather to mourn the man who bestrode the pop world for 25 years

The sensational, yet tragic life of Michael Jackson, the supremely-gifted pop singer who emerged from childhood stardom to become one of the most influential and infamous celebrities of modern times, was cut short late last night in the chaotic emergency room of a Los Angeles hospital. He was 50.

Doctors pronounced the King of Pop dead at around 2.30pm local time (10.30 GMT), after he suffered a massive cardiac arrest at his rented chateau-style home in the Holmby Hills area of the city, shortly after mid-day. He had been discovered in a coma when emergency services arrived at the scene. The death of the once-dazzling performer came weeks before he was due to attempt to re-launch his career with a series of 40 comeback concerts in London.

Jackson was reportedly taken ill as he prepared to leave home and drive to Burbank, where he was rehearsing the new show that was to mark his return to the stage for the first time in almost ten years. He was hoping to rehabilitate his reputation following a series of freakish scandals that had left him bankrupt, with his private life and reputation in tatters.

Exact circumstances of the incident were still unclear at time of going to print. However paramedics reported being called to a 7 bedroom, 13 bathroom house on Carolwood Drive, just off Sunset Boulevard, at 12.21pm Los Angeles time. The French-style property, boasted 12 fireplaces and a cinema, and was being rented by Jackson for $100,000 [£60,000] a month.

An ambulance arrived less than five minutes later and discovered the singer unconscious and in full cardiac arrest. Unconfirmed reports said he had been working out in the home's gym with Lou Ferrigno, the actor who played the Incredible Hulk and had been helping him get in shape for the forthcoming concerts.

The ambulance was logged leaving the property at 12.32, and doctors performed CPR throughout the 2 mile, six minute journey to UCLA medical centre. However, they were unable to revive him and he never regained consciousness.

Large crowds were gathering outside the hospital last night, with many carrying flowers and banners, and some mourners wearing fancy dress costumes. The sudden news of Jackson's death shocked the world, crashed news websites, and prompted tens of millions of viewers to switch to rolling news channels. At one point, almost a dozen TV helicopters were hovering above the hospital.

Scores of policemen arrived at the scene, and mounted a chaotic effort to secure the building. Family members were on the scene from shortly after Jackson's admission. Joe Jackson, the star's father, told showbiz website TMZ.com, which broke the story, that he had been rushed to hospital that "he is not doing well."

The website later broke the news that the singer had died. TMZ added that his sister LaToya Jackson ran into the hospital sobbing. Also at the venue were Jackson's three children, who he has brought up alone: Michael Joseph Jackson Jr, Paris Michael Katherine Jackson, and Prince Michael Jackson II, who is known as "Blanket."

Jackson's death brings a tragic conclusion to a long, bizarre, sometimes farcical decline from his commercial peak in the 1980s, when he was popular music's premier all-around performer, and dazzled the world with the haunting reach of his artistic possibilities.

In public, he was perhaps the most exciting artist of his generation, known for crotch-grabbing dance moves and his high-pitched. His single sequinned glove, tight, military-style jacket and aviator sunglasses were trademarks second only to his ever-changing, surgically altered appearance.

In terms of his earnings and fame, he ranked alongside Elvis Presley and the Beatles as the biggest pop sensations of all time. In fact, he united two of contemporary music's biggest names when he was briefly married to Presley's daughter, Lisa Marie.

Yet in private, he became an increasingly tortured soul, who perhaps never recovered from being denied a normal childhood. At the height of his fame, he lived at a bizarre Hearstian theme park called Neverland where he slept in oxygen tents, held hands with a chimpanzee called Bubbles, and (at a time when it didn't have dubious connotation) invited thousands of children to play.

As years went by, he became an increasingly freakish figure – a middle-aged man-child weirdly out of touch with grownup life. His skin became lighter, his nose narrower, and he spoke in a breathy, girlish voice. He surrounded himself with children, and became an object of tabloid infamy.

In 2005, he was tried and then cleared of charges he molested a 13-year-old cancer survivor at Neverland in 2003. He had been accused of plying the boy with alcohol and groping him. Jackson's financial problems finally caught up with him in November, after four years on the road, living in luxury hotels in Bahrain, Ireland and Germany, mostly at other people's expense, when Neverland went into foreclosure. In a bid to clear his debts, creditors persuaded him to announce a series of 50 concerts at the O2 arena in London, which sold out in hours when tickets went on sale.

The shows were heralded as the first step in an unlikely career renaissance that would ultimately encompass a three-year world tour, a new album, movies, a Graceland-like museum, musical revues in Las Vegas and Macau, and even a "Thriller" casino. It would wipe out his massive debts, variously estimated at between $60m and $200m, and allow him to retire in comfort.

However cynics always doubted Jackson was physically capable of a comeback, which was originally scheduled for 8 July. Attention may now turn to whether it was responsible for the promoters to let Jackson carry out the tour. In May, Randy Phillips, the head of AEG who had promoted the concerts, denied tabloid reports that he was suffering from skin cancer. "He's as healthy as can be; no health problems whatsoever." However days later, AEG was forced to cancel the first four shows of the run, blaming "technical issues." The opening night was moved to July 13.

Quincy Jones, who helped arrange Thriller and produced Off the Wall album, told reporters: "I am absolutely devastated at this tragic and unexpected news. For Michael to be taken away from us so suddenly at such a young age, I just don't have the words. I've lost my little brother today, and part of my soul has gone with him."