Folk legend Pete Seeger, who passed away last night at the age of 94, is one of the voices in "Freedom Summer," the new documentary from Stanley Nelson ("Jonestown: The Life and Death of Peoples Temple") that just had its world premiere at the Sundance Film Festival. The film, about the hard-fought civil rights battles in the summer of 1964 in segregated Mississippi, will air on PBS as part of "American Experience" on June 24th. The network today released a clip, below, featuring Seeger and Mississippi resident Roscoe Jones talking about a concert Seeger did in a church in Meridian, MS that summer, during which the performer got word that the bodies of missing, murdered civil rights workers James Chaney, Andrew Goodman and Michael Schwerner had been found. The interview was shot in April of last year -- take a look: