Tren de Aragua was originally a prison gang that Hector Guerrero Flores turned into a "transnational criminal organisation", according the US state department, which is offering a reward of $5m for information that could lead to his arrest. Guerrero Flores, 41, was in and out of Tocorón for more than a decade.

The Trump administration has invoked a 227-year-old law, the Alien Enemies Act, to target Tren de Aragua, a gang with its roots in the prisons of Venezuela. Who are they and how wide is their reach?

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.