 Between 1972 and 1974, it is documented that the Bureau planted over 500 bugs without a warrant and opened over 2,000 pieces of personal mail.More recent targets of covert action include the American Indian Movement (AIM), Earth First!, and Committees in Solidarity with the People of El Salvador.Documents released under the FOIA show that the FBI tracked the late David Halberstam—a Pulitzer Prize-winning journalist and author—for more than two decades.