LANSING, Mich. (AP) — Michigan health officials say there have been 19 Detroit-area deaths since July that could be related to carfentanil, a deadly painkiller used to tranquilize elephants.

The state’s Human Services Department announced Thursday that the deaths were reported by the Wayne County Medical Examiner. In all cases, they say the drug was combined with other opioids including heroin.

And over the past week, officials say there has been an increase in severe opioid-related toxicity in southeast and central Michigan reported to Michigan Regional Poison Control Center. Officials say many of the patients had symptoms consistent with carfentanil.

Carfentanil also was suspected but not confirmed in a Kent County case last month. The drug is sometimes sold in pill form. It’s been linked to fatal overdoses in Ohio.

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