Officials: Michael Jackson's Doctor Bought Powerful Anesthesia

In the ongoing investigation of Michael Jackson's death, a law enforcement official said that federal drug agents found evidence that the late singer's personal physician, Dr. Conrad Murray, legally purchased a powerful anesthetic from a Las Vegas pharmacy.

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Murray told investigators he administered a fatal dose of the anesthetic propofol to Jackson in his rented Beverly Hills mansion in the hours before he died, the official told The Associated Press. (Propofol is only supposed to be administered by anesthesia professionals in hospitals.)

Murray's attorney Edward Chernoff said he had no immediate comment on Tuesday but has said previously that Murray never gave Jackson any drugs that "should have" killed him.

Last month, Murray fully cooperated with DEA agents as they searched his Las Vegas home, office and a storage unit in Houston, Texas, in relation to the probe.

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Jackson's official cause of death will not be revealed until the final autopsy report is released by the Los Angeles County coroner's office and the manslaughter investigation is complete, an official said Monday. Meanwhile, the Associated Press reports that a Jackson tribute concert organized by Jermaine Jackson will take place Sept. 26 at a palace in Vienna, Austria. (According to Jermaine, the venue was chosen because his brother "loved castles.")

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Reps for Madonna and Whitney Houston denied media reports they would perform at the show.