UFC Hall of Famer Stephan Bonnar's Cause of Death: Accidental Fentanyl Overdose

UFC Hall of Famer Stephan Bonnar died from an accidental drug overdose due to fentanyl, paraflurofentanyl, and mitragynine intoxication, according to the Clark County coroner's office. Fentanyl is a synthetic opioid that is up to 50 times stronger than heroin and 100 times stronger than morphine. UFC president Dana White described Bonnar as "one of the most important fighters to ever compete in the octagon" for his classic UFC Hall of Fame fight against Forrest Griffin in April 2005.