CHICAGO (AP) – Fake marijuana likely contaminated with rat poison has killed three people in Illinois and sickened more than 100 others in the last month.

The federal Centers for Disease Control and Prevention says most cases are in Illinois but a few others have occurred in Indiana, Wisconsin, Missouri and Maryland. It warns doctors nationwide to look out for patients with severe unexplained bleeding.

Authorities say several patients and samples of fake weed from Illinois have tested positive for a lethal ingredient often used in rat poison.

Fake marijuana contains chemicals that produce a marijuana-like high. They’re sold in some convenience stores as liquids for use in e-cigarettes or in dried plant material that can be smoked. Nicknames include K2, Spice and Kush.

Illinois reported seven more illnesses on Tuesday.

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