The Algonquin/Lake in the Hills Fire Protection District and the Algonquin Police Department on Sunday said they were aware of a chemical smell in the air and are monitoring the situation.

The smell is being reported all over social media, with posts from Illinois Storm Chasers and others.

The fire district posted information on its Facebook page Sunday morning after multiple 911 calls were received “regarding an unknown odor described as a chemical or burning electrical smell in the air,” according to the post.

Just before 10 a.m., the post noted the complaints had been ongoing “for approximately the last 12 hours and span a wide area, from central Illinois through Indiana and as far north as the Wisconsin border. The source of the odor appears to be coming from a distance quite south of here.”

The source of the odor is unknown, and fire officials are actively monitoring the situation while “coordinating with regional partners and other agencies to gather information,” the post states

Residents should seek medical attention if experiencing symptoms including difficulty breathing, dizziness, nausea, or irritation, and only call 911 if there is an immediate emergency or safety concern, the post goes on to say.

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