As investigators wait for the results of toxicology tests on Michael Jackson to determine the singer's cause of death, older sister LaToya Jackson has come up with her own theories about what felled her 50-year-old brother. In an interview with England's Mail on Sunday, LaToya blames her brother's death on a shadowy cabal of hangers-on who she alleges manipulated Michael into signing up for a 50-date engagement at the O2 Arena in London and cutting him off from his family and friends.

"I believe Michael was murdered, I felt that from the start. Not just one person was involved, rather it was a conspiracy of people," said LaToya, 53, a onetime Playboy model who was estranged from the Jackson clan for a time in the early 1990s, after she claimed that she believed Michael acted inappropriately with children. She later said she was manipulated into the statement by her controlling ex-husband.

Last week, the chief of the Los Angeles Police Department said it is still possible that the investigation into Jackson's death could turn into a homicide case, depending on the results of toxicology tests.

"He was surrounded by a bad circle. Michael was a very meek, quiet, loving person. People took advantage of that. People fought to be close to him, people who weren't always on his side," LaToya said, not blaming anyone in particular, but referring to a "shadowy entourage" who supplied her brother with prescription drugs. Since his death, a number of stories have emerged detailing Jackson's alleged addiction to prescription medications, including an intravenously delivered surgical anesthetic not intended for private use that the singer is said to have used as a sleep aid.

LaToya told the paper that less than a month ago, she thought Michael was going to die before his London shows — which were slated to kick off on Monday (July 13) — because "he was surrounded by people who didn't have his best interests at heart."

She said Michael never believed he would live to be an old man and feared he would die in his 50s. She suspected he was worth more dead to the "greedy people" around him than alive. LaToya also allegedly revealed some new information about her brother's death, including her claims that he was not found on a bed, as reported, but inside the nearby bedroom of his personal physician, cardiologist Conrad Murray, who she said "disappeared" when she tried to question him at the hospital. Murray has been interviewed by investigators in the case and police have said he is not a suspect in Jackson's death. LaToya said an IV drip was beside the bed where her brother was found and oxygen canisters lined the walls.

"They got him hooked on drugs," LaToya said, vowing to file a civil lawsuit against anyone the family believes could be responsible for Michael's death. "He was pure and clean, and then drugs came back into his system. I think it shocked his system so much it killed him." She said he had needle marks on his neck and on his arms — which could be signs of intravenous drug delivery — and that he was strong-armed into doing the grueling 50-date string of O2 shows and kept away from his family during the long rehearsals for the gigs.

"It's impossible even for a healthy person to do that many shows," she reportedly told the paper. "Michael was fragile. He always wanted to believe the best of people. But he was meek. In the last few months, he became isolated. I believe the staff were given strict instructions that if any of the family called, not to tell him. And if any of the family came by, not to let them in." The Jackson family has not responded to MTV News' requests for comment on LaToya's interview.

"I am going to get down to the bottom of this," LaToya vowed. "I am not going to stop until I find out who is responsible. Why did they keep the family away? It's not about money. I want justice for Michael. I won't rest until I find out what — and who — killed my brother."

While Jackson's ex-wife, Debbie Rowe, long ago signed away custody of the couple's two children, LaToya said she would also fight what appears to be a renewed effort by Rowe to gain custody of Prince Michael and Paris. "These are not Debbie's kids," she said. "They don't even know she's their mother. Like everyone else in his life, she was motivated by money. She has always said she's not their mother. My understanding is that she will now go after the kids. I know a few things about Debbie, and I will prevent that from happening." A custody hearing on the matter has been pushed back until next Monday (July 20).

For complete coverage of the life, career and passing of the legendary entertainer, visit "Michael Jackson Remembered."

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