In April 1961 ~1500 CIA-trained Cuban exiles launched the Bay of Pigs invasion of Cuba (Invasión de Playa Girón) in an attempt to overthrow the government of Fidel Castro.
Without any of the promised air support from the United States, the operation failed completely. Cuban forces killed 200 rebels and captured 1,197 in less than 72 hours.
A single copy of a CIA report written by inspector general Lyman Kirkpatrick was made public in 1998.
Source: Wikipedia