HUNTINGTON, W.Va. (AP) — Authorities say the heroin that led 27 people to overdose in a five-hour span in a single West Virginia city had been mixed with the powerful painkiller fentanyl.

The Herald-Dispatch of Huntington reports that investigators for the first time detailed the potency of the concoction in a federal indictment Tuesday.

Twenty-two-year-old Bruce Lamar Griggs of Akron, Ohio, is charged with drug distribution in connection to the Aug. 15 spate of overdoses in Huntington. At least one man died.

Griggs was arrested by Tallmadge, Ohio, police officers late last month and is now in federal custody.

The Centers for Disease Control and Prevention says fentanyl is an opioid that is about 50 to 100 times more powerful than morphine.

The indictment does not mention whether Griggs has an attorney.

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