HARRISBURG, Pa. (AP) — The district attorney is investigating and putting out an alert after 20 people overdosed on synthetic marijuana in and around Pennsylvania’s state capital city.

Dauphin County District Attorney Ed Marsico says the drug users overdosed over the course of two days last week in the Harrisburg area.

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Emergency room doctors are reporting users have experienced advanced stages of delirium and some have had to be revived, including one that wound up in intensive care.

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Investigators say the synthetic pot in question was packaged with the word “Darkness.” They suspect some chemical or other substance may have been added to the synthetic pot.

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