Here's what to know about the mega-prison in El Salvador where hundreds of immigrants were transferred after President Trump signed a wartime declaration - The Alien Enemies Act of 1798 - last used during World War II to target Venezuelan gang members.

The United States is set to pay El Salvador $6 million to imprison 300 alleged members of the Venezuelan Tren de Aragua gang that it deports to the Central American country, for one year, the Associated Press reported on Saturday,

The administration won’t identify those moved — or say whether the Alien Enemies Act, which briefly sped up some deportations, played any role.