Authorities reportedly also found a journal written by the late actor and are looking into it in hope to find clues about his death.
An autopsy performed on Philip Seymour Hoffman returned inconclusive. New York City medical examiners' office said on Wednesday, Feb 5 that more tests would be needed to determine the cause of the actor's death.
"Our examination has been concluded but the results are inconclusive," Julie Bolcer told The Times. "We are awaiting results and additional studies." There is no timetable on when the autopsy will be finished.
Hoffman was found dead in a bathroom on Sunday with a needle in his left arm and drug paraphernalia nearby. Police suspected drug overdose and found at least 50 packets of heroin in his Manhattan apartment. Early tests found heroin samples in the packets but police are also testing whether the drug was mixed or tainted with anything else.
There has been a strain of extremely potent heroin that has killed dozens of people on the East Coast just last month. Some of the heroin are meant for terminal cancer patients, containing fentanyl as one of the ingredients and having 100 times more power than morphine. However, a police official said that the heroin found in Hoffman's apartment tested negative for fentanyl.
The authorities reportedly also found evidence of other substance abuse such as unused syringes, a charred spoon and a lot of prescription medication including one that is used to treat heroin addiction. Along with the items, detectives found a rambling journal of the 46-year-old actor in the apartment. They have reviewed the contents in hope to shed some light on the circumstances of his death, but the details are kept under wrap.
Four people have been arrested on drug charges in relation to Hoffman's death. They allegedly possessed 350 packets of heroin among them and had Hoffman's contact number.