Manager: Janet Jackson “Is Grief-Stricken”

Janet Jackson, who was in Atlanta at the time of brother Michael Jackson's death, has arrived in Los Angeles. She was photographed at the Van Nuys airport early Friday.

"Janet Jackson is grief-stricken and devastated at the sudden loss of her brother," her manager Kenneth Crear told Thursday. "She is in pre-production on a film and is flying immediately to California to be with her family."

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The family are currently gathered at Michael's rented home in Los Angeles, where the King of Pop went into cardiac arrest Thursday, a source tells

"They are stunned," Brian Oxman, the Jackson family attorney for 20 years, tells Us of the family's state. "They are barely even able to speak about it."

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Oxman was with the family at the hospital (mother Katherine, brothers Randy and Jermaine, and sister Latoya, arrived separately at the hospital for vigil). "They were silent, they were crying, they weren't really able to say anything," he says. "They just were stunned by this whole experience."

Jackson's autopsy is underway, though results aren't likely to be final until toxicology tests could be completed (which could take weeks).

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Though some reports claim Jackson may have overdosed on Demerol, Oxman tells Us he couldn't comment on the types of medications Jackson was taking.

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"It is something which is private to Michael, and we'll have to wait for the toxicology reports before we jump to any kind of conclusions," he said. "I only know that I warned that his day may come. And lo and behold, here we are."

Jackson suffered cardiac arrest at his rented L.A. home Thursday and was pronounced dead at 2:26 p.m. PST.

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