The Tren de Aragua has been on the radar of U.S. authorities for years. But it wasn’t until Trump campaigned for a second White House term that the gang became widely known in the U.S., as he and his allies turned the group into the face of the alleged threat posed by immigrants living in the country illegally.

Despite the president designating the group as a terrorist organization, almost all of the 37 men flagged by Chicago police as possible members have faced only drug charges and citations for driving infractions.

Trump issued an executive order to use the Alien Enemies Act to target Venezuelan migrants with ties to the Tren de Aragua gang.