BRIDGETON, N.J. (AP) — Authorities in Cumberland County are warning heroin users there’s a potentially deadly drug on the street.

Investigators last week uncovered a baggie containing pure fentanyl. The synthetic opiate is often mixed with heroin or cocaine and can be fatal in its pure form.

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The baggie was stamped “Egg Nog.”

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The prosecutor’s office says drug dealers often change stamps so there may be bags with a high concentration of fentanyl on the streets with different stamps or no stamps at all.

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