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.

The baggie was stamped “Egg Nog.”

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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