Hawaii health officials are warning that a batch of cocaine mixed with fentanyl is circulating in Honolulu, a serious danger for anyone using street drugs.

• Police responded to several suspected overdose calls in Waikiki on Thursday.
• Officials say the tainted supply traces back to Mexican cartels cutting drugs with fentanyl to make more money.
• It is not yet confirmed the Waikiki victims thought they were taking cocaine.
• The advice is blunt: assume every illegal drug contains fentanyl.
• Naloxone, which reverses an overdose, is stocked at 77 locations across the state, and witnesses should call 911 right away.

Outlook: More overdoses are likely until the contaminated batch works its way out of circulation.