The Los Angeles Times reported that Jackson was not breathing when paramedics arrived. Captain Steve Ruda told the paper that Jackson was not breathing when paramedics responded to a call at Jackson's home around 12:26 p.m. PT.
A Jackson family member reportedly told TMZ that the singer is in "really bad shape" and his brothers are headed to UCLA. Jackson's father, Joe, reportedly told the site that his son is "not doing too well."
MTV News was unable to reach representatives for Jackson at press time.
The Los Angeles Times and TMZ reported late Thursday afternoon that Jackson had died, but those reports were unconfirmed at press time. A spokesperson at UCLA Medical Center declined comment when contacted by MTV News.
If the reports are accurate, this development will almost certainly have an impact on the singer's 50 scheduled concerts in London, which are scheduled to begin on July 13. The concerts all sold out within hours of the tickets going on sale.
The residency, called This Is It, is scheduled to continue through February. Jackson has said these are the last shows he'll play in London.
However, the singer has been dogged by a $40 million lawsuit filed earlier this month by promoter AllGood Entertainment Inc., claiming breach of contract and fraud in an attempt to stop Jackson from performing in London. The New Jersey-based company filed the suit in federal court in New York stating that it signed a deal with Jackson's manager, Frank DiLeo, in November 2008 that commits the singer to appear at a Jackson family reunion concert in the U.S. this summer.
AllGood CEO Patrick Allocco told MTV News that the contract was for a concert that was originally scheduled to take place this July. "The date we now have on hold is July 3 in Cowboy Stadium in 2010," Allocco said, adding that the contract stipulates that Jackson cannot perform individually before the AllGood show or for three months after the July event.
Jackson, who had been rehearsing for the London shows in Los Angeles, has claimed he never personally signed the papers for the family-reunion show, and AEG Live CEO Randy Phillips has called the AllGood claims "meritless." But Allocco said, "Frank DiLeo is clearly the manager of [Michael] Jackson now, and he signed the deal on his behalf."
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[This story was originally published at 5:32 pm E.T. on 6.25.09]