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?

Venezuelan President Nicolas Maduro sent 11,000 soldiers to storm the Tocorón Prison in the northern state of Aragua. But they were not dispatched to quell a riot. The troops were taking back control of the prison from a powerful gang that had turned it into something of a resort,