SINCE his death, MICHAEL JACKSON’s children have been hiding a secret murder bombshell that is now set to explode in court, say sources.

In a stunning world exclusive, close family sources tell The ENQUIRER that sensation­al testimony from Prince, 16, Paris, 15, or Blanket, 11, could convince a jury to award Michael’s heirs a whop­ping $40 billion in the wrongful death lawsuit they’ve filed against concert promoter AEG Live.

In the weeks before his drug-related death on June 25, 2009, sources say 50-year-old Michael repeatedly warned his children to stay away from the “devils” of AEG.

“In multiple private conversations with his kids, Michael secretly confessed that he feared for his life,” one of the close sources told The ENQUIRER on the eve of the civil court trial. “Michael even used the words, ‘People are trying to kill me.’ Another time he emotionally told them, ‘I’m worth more dead than alive to them.’

“Michael’s children have been hiding this shocking murder secret ever since, and it’s clear they could throw this trial into chaos with their testimony!”

In the lawsuit, Michael’s three children, led by their legal guardian, Jackson’s mother Katherine, accuse AEG of “negligence and breach of contract” in hir­ing and supervising Dr. Conrad Murray, who’s been convicted of involuntary manslaughter in Jackson’s death. The suit claims AEG put “its desire from the tour over the health and safety of Michael Jackson,” and seeks damages related to Michael’s potential earnings if he’d lived.

While the loss of earnings is projected at $1 billion to $5 billion, the damages have been calculated at a whopping $40 billion!

AEG denies the accusations and contends Dr. Murray was hired by Michael himself. As a result, AEG says it had no responsibility for Dr. Murray’s treatment of the singer.

Chillingly, the King of Pop has seemed to point a finger at AEG from beyond the grave – with his children claiming he repeatedly warned them about AEG staffers, said another Jackson family insider.

“Prince and Paris told their attorneys they remem­ber their father telling them to be careful of ‘those men’ from AEG because they were dangerous,” said the source.

“Michael called the AEG guys ‘devils.’ When they came over, Michael made sure the nanny kept the children occupied in another part of the house. Michael also told the children that the only thing those men cared about was money, and they’d do anything for it.”

In yet another bombshell, The ENQUIRER has learned that secret surveillance reveals explosive new evidence of disturbing goings-on at Jacksons’ rented mansion in Holmby Hills, Calif.

“There was a lot of suspicious activity,” top Hollywood private investigator Dan “Danno” Hanks, who secretly had Jackson’s house under surveillance in the weeks leading up to his death, told The ENQUIRER.

 “I saw several cars with out-of-town license plates, including some from Nevada and Texas, coming and going from the home. We were able to confirm that some cars carried Jackson bodyguards. As for others, we just don’t know.”

With so many unknown indi­viduals at the Jackson residence, it’s possible that someone besides Dr. Murray was present on the night Jackson was stricken, said Hanks.

“The trial could explode if it’s uncovered that Dr. Murray ei­ther had a secret accomplice or that another person was present unbe­knownst to him,” said Hanks, who claims to have been a confidential informant for the DEA and FBI.

“Based on my observations, either scenario is possible due to the num­ber of suspicious people at the house in the days before Michael’s death.”

Testimony from those individu­als could be key at the trial, Hanks added.

“One of them may hold the secret to Michael’s death,” he said.

A line-up of stars are expected to testify, including TV personality Sharon Osbourne, singers Diana Ross and Prince, Jackson’s ex-wife Lisa Marie Presley, music producer Quincy Jones and filmmaker Spike Lee.

Meanwhile, Michael’s father Joe has also said that he’s certain foul play was involved in his son’s death. And the star’s sister La Toya states flatly: “Michael was murdered. We don’t think just one person was in­volved. Rather, it was a conspiracy of people. I feel it was all about money.”

Jason Pfeiffer, who worked for Michael’s dermatologist in L.A., recently told a British newspaper: “The last time I saw Michael, he was saying his goodbyes to everyone in the office. It was like he knew he was never coming back.”

With $40 billion at stake, the civil trial will most certainly get ugly, said nationally known New York attorney Peter Gleason, who recently defended “Manhattan Madam” Anna Gristina.

“There will be a lot of mudslinging from both sides,” said Gleason, who reviewed the suit for The ENQUIRER. “If Michael’s chil­dren testify about what their father told them and what they witnessed, it will play to the hearts of the jury, and put AEG on the defensive. The family certainly could make the case that AEG may have wanted harm to come to Michael if they thought the concert tour was going to be a bust.

“But it’s conceivable AEG could turn the tables on the family and make outrageous accusations that the family stood to profit the most from Michael’s death.

“Like Elvis Presley and Marilyn Monroe, Michael was certainly worth more dead than alive!”

Evidence, such as previously un­known e-mails and texts between AEG executives and others could also become public, he said, adding: “This has the makings of an O.J. Simpson-like trial with bombshell secrets and dubious murder-plot scenarios play­ing out!”