Initial Hoffman Autopsy Results Inconclusive

UPDATE: The New York City Medical Examiner's office said Wednesday that more tests are needed to determine Philip Seymour Hoffman's exact cause of death. Police have been investigating his death as a suspected drug overdose, but coroner spokeswoman Julie Bolcer announced there is currently no timetable for the late actor's autopsy to be fully completed. Toxicology and tissue tests are typically done in such cases, but she declined to discuss the pending tests.

Four people, suspected by police to possibly be connected to the drugs found in Hoffman's Manhattan apartment, were reportedly taken into custody on Tuesday for questioning by the New York Police Department.

On Sunday, February 2, police were called to Hoffman's apartment where they found the late actor's body in the bathroom. The Oscar winner was 46. According to law enforcement sources, Hoffman had a syringe in his arm.

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Police on the scene discovered dozens of envelopes, filled with heroin, and several empty containers they believe previously contained the narcotic.

This discovery led to a city-wide search for the dealers responsible for selling Hoffman the drugs. The four people being questioned were found during that investigation, according to CNN.

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Days before Hoffman's death, police in Maryland revealed that a bad batch of heroin, tainted with another powerful narcotic called fentanyl, had killed 37 people since September. Twenty-two people in Pennsylvania died from fentanyl-tainted heroin last month.

Some speculated that Hoffman could have died from the same tainted heroin, however, preliminary tests showed that the heroin found in his apartment did not contain the deadly additive. More thorough testing will be conducted.