Philip Seymour Hoffman's cause of death has been revealed as "accidental acute mixed drug intoxication," the medical examiner announced Feb. 28 Credit: Jon Kopaloff/FilmMagic

Philip Seymour Hoffman's official cause of death has been established nearly four weeks after his death. The late actor, 46 when he passed away earlier this month, died of "accidental acute mixed drug intoxication, including heroin, cocaine, benzodiazepines, and amphetamine," the New York City Office of the Chief Medical Examiner confirmed to Us Weekly on Friday, Feb. 28.

As previously reported, Hoffman was found dead with a hypodermic needle in his arm on Feb. 2. Police said at the time that as many as 65 bags of unused heroin were found in his West Village apartment; there were also used syringes, prescription drugs, and drug paraphernalia.

An initial autopsy on the Oscar winner's body just days after his death produced inconclusive results. At the time, a spokesperson for the medical examiner's office said that cause of death was "pending further studies," including a full toxicology report.

Hoffman's history with addiction was well-known. In May 2013, he entered rehab for a 10-day stint after relapsing following more than 23 years of sobriety.

He is survived by his three children, son Cooper and daughters Tallulah and Willa, with partner Mimi O'Donnell.