We finally have some answers about what lead to Tom Petty's death on Oct. 2. Tom's original cause of death was listed as "deferred," and now, nearly four months later, his family can finally get some closure. The legendary musician was killed by an accidental drug overdose, according to the autopsy report obtained by TMZ on Jan. 19.

According to the L.A. County Coroner, several of Tom's organs began failing due to "mixed drug toxicity." Tom had been taking several medications prescribes for ailments including emphysema, a bad knee, and a fractured hip. In his blood, doctors found oxycodone (Oxycontin), temazepam (Restoril), alprazolam (Xanax), citalopram (Celexa), acetyl fentanyl, and despropionyl fentanyl.

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Tom (third from left) with the Heartbreakers in 1976.

Fentanyl has been blamed for the deaths of several musicians, including Prince and Lil Peep. The opioid is considered more dangerous than heroin if abused, and fentanyl overdoses were declared a public health crisis in Canada in 2015. Tom's family thinks that his hip was to blame for the overuse of prescription drugs. He insisted on touring despite being injured at 66 years old, and on the day that he had his heart attack and died, the hip became full-on broken and excruciatingly painful. He was using Fentanyl patches and pills to try to dull the pain. Tom also suffered from coronary artery atherosclerosis, which likely lead to his heart attack.

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Tom in 2016.

Tom was admitted to the hospital on Oct. 2, 2017, after having a heart attack, and sadly passed away just hours later, leaving the music world devastated. We hope that this new info can finally help his family get some closure.