Authorities in three states have made arrests in connection with individuals impersonating Immigration and Customs Enforcement (ICE) officers, as tensions rise amid a nationwide immigration crackdown.

The federal Bureau of Prisons is accepting into their facilities thousands of immigrants detained by the Homeland Security Department, a highly unusual move that raises significant legal and logistical questions.

On Monday, the Florida Highway Patrol conducted a joint operation with federal immigration officers in Jefferson County to round up 12 people believed to be in the country illegally, one of a number of raids performed around the country as the Trump administration ramps up its plans for mass deportation.

President Donald Trump’s administration is using federal prisons to detain some people arrested in its immigration crackdown.