Here is a very rare set of civil defense announcements from 1961 that would have aired on WCCO-Radio in Minneapolis, Minnesota, in the event of a probable or actual enemy (nuclear) attack. These announcements were pre-recorded by WCCO announcers Howard Viken, Dick Chapman, and Governor Elmer Andersen:
"THE TWILIGHT ZONE"
SEEMS EERILY REALISTIC
AFTER LISTENING TO THE
1961 WCCO CIVIL DEFENSE BULLETINS: