The Trump administration says the group should be treated as an invading force. Critics say it’s a pretext for the administration’s anti-immigrant narrative.

Tren de Aragua, a gang born out of a Venezuelan prison, is a loose network that doesn’t operate like groups typically considered terrorist organizations.

The Trump administration has sparked controversy with its move Sunday to deport 261 people, some of whom it alleges are members of the Venezuelan gang Tren de Aragua, to an infamous maximum-security prison in El Salvador.