The cause of the 46-year-old film and stage star's death will not be determined until additional tests, including toxicology panels, are completed, which could take days or weeks, the office told the Hollywood Reporter Wednesday.
Hoffman, who had a history of drug addiction, was found dead Sunday morning, lying on the bathroom floor of his Manhattan apartment with a needle in his arm.
Dozens of envelopes of heroin, as well as used and unused syringes, were found in the flat, police have said.
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