Authorities say the synthetic opioid carfentanil has been responsible for at least six deaths in a Maryland county over a six-week period.
The Capital Gazette reports Anne Arundel County police say that six men between the ages of 19 and 54 died between April 1 and May 14 from overdoses on drugs the Office of the Chief Medical Examiner determined to include carfentanil.
The Drug Enforcement Administration considers the opioid to be 10,000 times more potent than morphine. Carfetanil is commonly used as a tranquilizer for large animals.
County health department directors Fran Phillips says it's possible carfentanil could have played a role in more deaths, as 25 fatal overdoses are awaiting review.
Police spokesman Lt. Ryan Frashure says no arrests have been made in connection with the drug.