A Hawaii crime boss who died in federal detention this month was killed by an opioid overdose, Honolulu’s medical examiner said Tuesday. Michael Miske, 50, died of “toxicity of fentanyl and para-fluorofentanyl,

Michael Miske Jr., who was convicted in July of operating one of the most notorious organized crime rings in Hawaiʻi, died of a fentanyl overdose in the Federal Detention Center, according to city officials. Miske, 50, was found dead in his cell Dec. 1.

The Honolulu Department of the Medical Examiner on Tuesday released the cause and manner of death for Mike Miske, the notorious organized crime leader who was found dead at the Federal Detention Center in Honolulu earlier this month.

The cause of death for a convicted crime boss who died at the Federal Detention Center in Honolulu has been released.

Nearly one month after convicted crime boss Michael Miske was found dead at FDC Honolulu federal prison, the Honolulu Medical Examiner’s office revealed his cause of death was due to fentanyl poisoning.

A medical examiner revealed a Hawaii crime boss died of an opioid overdose while in federal detention. Michael Miske, 50, was found unresponsive at the facility on December 1. It was later revealed that he died from "toxicity of fentanyl and para-fluorofentanyl,