Elzon Lemus is always on the road for work, traveling from one place to another.

But ever since federal immigration officers pulled the electrician over as he was driving to his first job of the day earlier this month in Nassau County, New York, Lemus has been on high alert, limiting his travel around town out of fear, he said — despite being a US citizen.

On June 3, Lemus says he was briefly detained during a traffic stop by federal agents because he resembled someone the agents were looking for, they told him and video from the encounter shows.

Lemus’ arrest, and other reports of American citizens being detained by immigration officials, highlights growing concerns over racial profiling and constitutional rights — for both the documented and undocumented — as the Trump administration’s broad mass deportation crackdown takes aim at people of all ages from children and families to suspected criminals by detaining people outside courtroom hearings, during traffic stops and in workplace sweeps.

It’s not legal for US Immigration and Customs Enforcement to arrest and detain US citizens, CNN legal analyst Joey Jackson said. But under certain circumstances, immigration officers can arrest citizens without a warrant if they witness an “offense against the United States” or a felony offense — otherwise, their powers are regulated to immigration matters, according to federal law.