(NEW YORK) -- An autopsy on the body of Oscar-winning actor Philip Seymour Hoffman is complete and the results have been deemed inconclusive pending the outcome of toxicology tests.
It's still believed Hoffman died from an accidental overdose, but the medical examiner wants to know more about what he ingested. Police found heroin and prescription pills in his apartment.
Police arrested four people on drug charges in connection with the death investigation of Hoffman, police told ABC News. Investigators received a tip that the four suspects -- three men and one woman -- were dealing heroin out of a New York City apartment. Police executed search warrants in three units of a Mott Street apartment and found more than 350 bags of heroin.
Robert Vineberg, 57, and Thomas Cushman, 48, were both charged with felony criminal possession of a controlled substance. Vineberg was also charged with criminal use of drug paraphernalia. Max Rosenbloom and Juliana Luchkiw, both 22, were charged with criminal use of drug paraphernalia, criminal use of controlled substance, and unlawful possession of marijuana.
The exact connection between the arrests and Hoffman’s death is unclear.
The arrests come four days after Hoffman's friend and screenwriter David Bar Katz found the actor unconscious inside his Manhattan apartment and called 911. Hoffman was pronounced dead at the scene.
Investigators recovered multiple types of drugs from Hoffman’s apartment, including dozens of bags of heroin, along with syringes, and various prescription medications, law enforcement officials have said.
Officials initially wondered if the heroin found at Hoffman’s apartment contained fentanyl, a potent synthetic morphine linked to 22 suspected overdose deaths in western Pennsylvania.
While official toxicology results are forthcoming -- they’ll likely be released next month -- preliminary tests of the heroin showed no traces of fentanyl, New York Police Department spokesman Stephen Davis told ABC News.
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