PORTLAND, Ore. (AP) — Night after night in Portland, tear gas and other crowd control devices have enveloped protesters and bystanders in airborne chemicals that settle on the ground, later to be washed into storm drains.

Amid allegations that people’s health and the environment are suffering the consequences, five environmental groups on Tuesday sued the Department of Homeland Security.

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The federal lawsuit says the U.S. government violated federal environmental law by deploying “an unprecedented amount of dangerous chemical weapons” without analyzing and documenting their environmental impacts beforehand, as required by the National Environmental Policy Act.