READING, Pa. (AP) – A district attorney in southeastern Pennsylvania has issued a public health warning in the wake of a series of drug overdoses believed to involve the same substance.

Berks County District Attorney John T. Adams says that a dozen people overdosed over the weekend in the city of Reading, West Reading borough, and Exeter and Rockland townships. Three died.

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He says the overdoses involved a substance believed to be cocaine laced with fentanyl or another opioid. The drugs were packaged in clear plastic packets or baggies.

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Detectives are awaiting the results of toxicology testing.

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