President Donald Trump says a "swift and lethal kinetic" US strike has killed Hector Rusthenford Guerrero Flores, whom he called "the infamous leader" of the Tren de Aragua gang.
Tren de Aragua has been labelled by the United States as a terrorist organisation.
Guerrero Flores was charged in a New York federal court with racketeering conspiracy and other crimes, including lending support to terrorists in crimes that stretched more than a decade, authorities announced in December.
