Christian girls who are fans of Michael Jackson take part in a candlelight memorial to commemorate him Friday in Karachi, Pakistan. Michael Jackson was due to make his triumphant return to the stage in London next month but instead his sudden death has left millions of fans feeling they’ve lost a lifelong friend.

Los Angeles ? Michael Jackson insisted that his concert promoter’s payroll include his personal physician, a financially troubled cardiologist who was with the entertainer when he collapsed.

Dr. Conrad Murray was hired by AEG Live to accompany the pop star to London for his comeback series of concerts, said AEG Live President and Chief Executive Randy Phillips.

“As a company, we would have preferred not having a physician on staff full-time because it would have been cheaper without the hotels and travel, but Michael was insistent that he be hired,” Phillips told The Associated Press. “Michael said he had a rapport with him.”

Jackson, who collapsed Thursday at his rented home in Los Angeles, appeared to have suffered a heart attack, a person with knowledge of the situation told The Associated Press. The person, who was not authorized to speak publicly and requested anonymity, said Jackson had a heart attack, which is a blocking of the arteries that deprives the heart of adequate blood.

Jackson’s brother Jermaine said Thursday that it was believed the pop singer went into cardiac arrest, an interruption of the normal heartbeat that can be caused by factors other than heart attack. The Los Angeles County coroner’s office, which completed its autopsy Friday, said there were no signs of foul play or trauma, but determining the cause of death will require further tests that will take six to eight weeks.

A heart attack could help explain why Jackson was in the care of a cardiologist while he went through vigorous training for an upcoming series of concerts in London: Heart attacks can indicate a long-term problem, such as heart disease. It would not necessarily rule out another factor, such as drug use, however.

Coroner’s spokesman Craig Harvey said Jackson was taking some prescription medications, but did not specify what they were.

Police seized Murray’s car the night before, saying they believed the car may contain drugs or other evidence, but have insisted that Murray has been cooperative and do not consider him a criminal suspect.

Records reveal years of financial troubles for Murray, who practices medicine in California, Nevada and Texas. His Nevada medical practice, Global Cardiovascular Associates, was slapped with more than $400,000 in court judgments, and he faces at least two other pending cases and several tax liens.

Phillips said AEG Live advanced Jackson money to pay for Murray’s services as part of the production costs. Phillips said he asked Jackson why he wanted Murray with him full-time.

“He just said, ‘Look, this whole business revolves around me. I’m a machine and we have to keep the machine well-oiled,’ and you don’t argue with the King of Pop,” Phillips said.

The promoter said that sometime in February Jackson submitted to “five-plus hours of physicals that the insurance underwriter insisted on. We were told he passed with flying colors.”

Phillips attended Jackson’s rehearsal at Staples Center on Wednesday night, when the entertainer was on stage for about three hours before leaving at 12:30 a.m.

“He was dancing as well or better than the 20-year-old dancers we surrounded him with,” the promoter said. “He was riveting. I thought we were home free. I thought this was going to be the greatest live show ever produced. He looked great.”

911 call

A 911 call released by fire officials Friday shed light on the desperate effort at the mansion to save Jackson’s life before paramedics arrived Thursday afternoon. Jackson died later at UCLA Medical Center.

In the recording, an unidentified caller pleads with authorities to send help, offering no clues about why Jackson was stricken. He tells a dispatcher that Jackson’s doctor is performing CPR.

“He’s pumping his chest,” the caller says, “but he’s not responding to anything.”

Asked by the dispatcher whether anyone saw what happened, the caller answers: “No, just the doctor, sir. The doctor has been the only one there.”

Jackson’s health had been known to be precarious in recent years, and one family friend said Friday that he had warned the entertainer’s family about his use of painkillers.

“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,” Brian Oxman, a former Jackson attorney and family friend, told NBC’s “Today” show. “The result was I warned everyone, and lo and behold, here we are. 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.

World mourns

The worldwide wave of mourning for Jackson continued unabated for the man who revolutionized pop music and moonwalked his way into entertainment legend.

“My heart, my mind are broken,” said Elizabeth Taylor, who was one of Jackson’s closest friends and married one of her husbands at a lavish wedding at the pop star’s Neverland Ranch in 1991. She said she had heard the news as she was preparing to travel to London for Jackson’s comeback show, and added, “I can’t imagine life without him.”

Hundreds made a pilgrimage to the Jackson family’s compound in Los Angeles, leaving flowers and messages of love. They did the same at his star on the Hollywood Walk of Fame and at the home in Los Angeles’ Holmby Hills where Jackson was stricken. Some camped out overnight.

In New York, people stopped at Harlem’s Apollo Theater, where Jackson had performed as a child with his brothers in one of rock’s first bubblegum supergroups, the Jackson 5.

At rehearsals for Sunday’s Black Entertainment Awards show, stars like Beyonce, Wyclef Jean and Ne-Yo were frantically revamping their performances in an effort to turn the evening into a Michael Jackson tribute.

Jackson imitators moonwalked at Mexico’s Angel of Independence, a prison in the Philippines organized a “Thriller” tribute dance, political leaders paid homage and French fans gathered at Notre Dame to sing and cry Friday as the world mourned the King of Pop.

Throughout Latin America, fans planned weekend tributes in town squares, while in Paris on Friday hundreds of Jackson fans sang, danced, cried and shouted out in grief at a gathering in front of the Notre Dame cathedral.

In London, shocked fans united at the Lyric Theatre, where a live show based on Jackson’s record-selling album “Thriller” is being performed, and waited for news about refunds for 750,000 tickets to his sold-out, 50-night run.

In the Philippines, prison security consultant Byron Garcia planned a tribute for Jackson today with inmates performing an encore of a famous video in which they do a synchronized dance to “Thriller.” The video has had 23.4 million hits on YouTube.