A coalition of pro-immigration organizations in the United States has sued the Trump administration over its requirement that millions of illegal immigrants in the country register with the federal government.

The American Civil Liberties Union, American Immigration Council, American Immigration Lawyers Association, National Immigration Law Center, RFK Human Rights, and CASA sued the Department of Homeland Security in federal court in Washington, D.C., on Monday. They alleged in their lawsuit that a rule the DHS published in March would turn the U.S. into a “show me your papers country.”