"He was working hard, setting the example, overseeing the choreography, kicking butt and taking names," said Johnny Caswell, president of CenterStaging Musical Productions Inc., a Burbank sound stage where Jackson rehearsed until late May. "He was ready to blow everybody out of the water. This was going to be the biggest extravaganza, entertainment spectacle ever."

Maryss Courchinoux, a 29-year-old Parisian who auditioned for the London tour, said that Jackson was involved in all stages of planning, including watching auditions.

The 50-year-old singer was preparing for a 50-concert series in London, kicking off July 13, when he collapsed at his rented home in Los Angeles. He was rushed to UCLA Medical Center where he was pronounced dead. The cause of Jackson's death is still undetermined, and won't be known for four to six weeks, but the Los Angeles coroner's office declared Friday evening that so far there are no medical signs of foul play or trauma to the body.

Coroner's spokesman Craig Harvey said Jackson was taking some prescription medications but declined to disclose or discuss them. He said Jackson's sudden demise became a coroner's case because there was no doctor to sign the death certificate. 

Coroner Investigator Jerry McKibben said Jackson's body has been released by the Los Angeles County coroner's office and was returned to the singer's family Friday night. No funeral plans have been announced.

"We're trying to pump him, he's not breathing," the caller is heard saying on the tape, released by Los Angeles fire officials Friday. "He's not responding to CPR, he's not responding to anything. Please hurry."

"We're on our way," the dispatcher responds, who then asks the caller, "Did the doctor see what happened?"

The caller can be heard asking the doctor what happened but gets no answer, and tells the dispatcher again to hurry.

Los Angeles police say they are looking for the doctor, who they hope will help in the investigation of Jackson's mysterious death. Los Angeles police spokeswoman Karen Rayner said police towed from Jackson's house a physician's BMW "because it may contain medications or other evidence that may assist the coroner."

Rayner did not know the physician's identity but said he was not the subject of a criminal investigation. The Los Angeles Times and The Associated Press reported the doctor is Dr. Conrad C. Murray, a cardiologist who practices in California, Nevada and Texas.

The autopsy on the body was completed by 1 pm local time. The results won't be final until more tests are completed.

Brian Oxman, a former attorney of Jackson's family and a family friend, said on NBC's Today show that he was concerned about Jackson's use of painkillers and he warned the singer's family about possible abuse.

"I said one day, we're going to have this experience. And when Anna Nicole Smith passed away, I said we cannot have this kind of thing with Michael Jackson," Oxman said.

"I don't know what caused his death. But I feared this day, and here we are."

Oxman claimed Jackson had prescription drugs at his disposal to help with pain suffered when he broke his leg after he fell off a stage and for broken vertebrae in his back.

Meanwhile, Jackson's famous friends reacted with shock and grief. "I can't stop crying. This is too sudden and shocking," said Supremes superstar Diana Ross, who helped launch Jackson's career. "I am unable to imagine this. My heart is hurting."

"When the autopsy comes, all hell's going to break loose, so thank God we're celebrating him now," Liza Minnelli told CBS' The Early Show by telephone.

Lisa Marie Presley, Elvis Presley's only child and Jackson's ex-wife, issued a sorrowful statement. "I am so very sad and confused with every emotion possible," she said in a statement. "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."

In an emotional post on her MySpace blog, Presley denied that her marriage to Jackson was a sham, as many have suggested, lamented that she had failed to save him from his fate, and recounted how Jackson himself predicted years ago that he would end up dying tragically like Elvis.

"The hardest decision I have ever had to make, which was to walk away and let his fate have him, even though I desperately loved him and tried to stop or reverse it somehow," Presley wrote in her blog. "All of my indifference and detachment that I worked so hard to achieve over the years has just gone into the bowels of hell and right now I am gutted."

Debbie Rowe, Jackson's second ex-wife and a former nurse for his dermatologist who bore two of his children, was said to be inconsolable. Her attorney, Iris Finsilver, released a prepared statement in which Rowe calls Jackson "a beautiful and loving soul."

(Rowe and Jackson married in 1996 and divorced in 1999, after Rowe gave birth to Prince Michael, 12, and Paris-Michael, 11. Jackson's youngest child, Prince Michael II, 7, nicknamed "Blanket," was born to a surrogate mother in Europe. He was the baby Jackson dangled from the fourth-floor balcony of a Berlin hotel, prompting criticism of Jackson's parenting around the world. The three children, who were at the hospital where Jackson was declared dead, are said to be staying with Jackson's mother, Katherine Jackson.)

President Obama was more restrained in his reaction to the death. After saying nothing about Jackson on Thursday, Obama's spokesman, Robert Gibbs, on Friday did not mention Jackson until asked about him at his regular White House briefing. Gibbs said the president saw Jackson as a spectacular performer and music icon whose life nonetheless had sad and tragic aspects. Gibbs said Obama sends his condolences to the late singer's family and fans.

Congress also reacted: The House of Representatives paused for a moment of silence Friday to mark Jackson's passing.

Jackson, 50, died Thursday at UCLA Medical Center in Los Angeles after becoming ill at his nearby Holmby Hills rented home. He had been preparing for a series of 50 concerts starting July 13 at London's O2 arena.

The cause of death was unclear, but his brother Jermaine Jackson said Thursday that he appeared to have suffered cardiac arrest. The official cause won't be known until after the autopsy.

Jackson's personal physician was with him when he was taken ill and attempted to resuscitate him, as did arriving paramedics, Jermaine Jackson said. He was unconscious when the ambulance delivered him to the hospital.

As word of his death spread, MTV switched its programming to play Jackson videos. Radio stations began playing marathons of his hits. Hundreds of people gathered outside the hospital. In New York's Times Square, a low groan went up in the crowd when a screen flashed that Jackson had died, and people began relaying the news to friends by cellphone.

Tributes to the fallen King of Pop are cropping up all over the globe, including at the legendary Apollo Theater. On Tuesday, the doors will open to the public so fans can see photos, view videos and hear Rev. Al Sharpton speak.

Elsewhere, a candlelight vigil will be held this weekend at the Motown studio in Detroit. In the Philippines, 1,500 inmates revive a choreorgraphed dance routine of Thriller, and French fans gathered at Notre Dame to pay homage.

Jackson, gifted from birth, famous since childhood and a figure of equal parts tragedy and success, had long demonstrated physical and mental frailty. But he was said to be working out and rehearsing at the Staples Center in Los Angeles in preparation for yet another comeback. The shows were to feature the elements that made him such a sensational performer — fabulous choreography, elaborate staging, and irresistible dance beats.

Longtime Grammy Awards producer Ken Ehrlich says Jackson was physically fit and in high spirits when they met Wednesday night to discuss an upcoming TV project. "He was really in good shape," Ehrlich says. "That's what's so upsetting. There was no doubt in my mind that he was ready to go, that these shows would be significant."

Ehrlich saw a half-dozen "signature Michael" numbers planned for what he described as a "terrific" show. "Seeing him do those moves again, you're struck by the impact he's had on the whole popular culture for 40 years."

Once the most popular musical entertainer in the world — his 1982 album Thriller is among the bestselling albums of all time, with an estimated 50 million sold — Jackson dominated his industry for years, breaking records and barriers as a performer who appealed to all races and cultures.

But his career had declined in more recent years as Jackson's appearance, behavior and personal life became more bizarre and his money problems and legal woes mounted. By the end, he was no longer the king, but was trying to regain his throne.

Contributing: Maria Puente, Kelley L. Carter, Edna Gundersen and the Associated Press

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