“There is no legal requirement that US citizens carry papers or have proof of their citizenship on them,” said an attorney at the ACLU of Northern California.

Federal law enforcement agencies are detaining US citizens who do not carry proof of their citizenship in what civil rights advocates describe as a flagrant violation of constitutional rights—and a top Trump administration official is claiming the government has the authority to do so.

A Somali-born Minnesota man was alarmed by the practice last Tuesday when immigration agents tackled him, handcuffed him, and arrested him, refusing to accept his REAL ID as proof of his legal residence in a video that was widely circulated on social media.

The man, who identified only as Mubashir, was placed into a chokehold and forced to his knees in the snow on his way to get food in Minneapolis’ Cedar-Riverside neighborhood, which has a large Somali population.