James, Jonathan and Mary Winnefeld this fall when they dropped their son off at the University of Denver for his freshman year.

(Courtesy James Winnefeld)

Retired Navy Admiral James "Sandy" Winnefeld says he had mixed emotions when he dropped his son Jonathan off this fall for his freshman year at the University of Denver.

The former vice chairman of the Joint Chiefs of Staff told Colorado Matters his son had recently undergone treatment for heroin addiction. Four days after that drop-off, Jonathan died from an apparent overdose of heroin laced with Fentanyl. 

Winnefeld recently started an organization called Stop The Addiction Fatality Epidemic or SAFE aimed at overcoming the nation's opioid epidemic. 

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