Because of poor planning and insufficient training, all eleven hostages were killed in addition to eight terrorists.  
Georg Sieber predicted this event, but was ignored because his scenarios were deemed preposterous. This event was responded to by Operation Spring of Youth and Operation Wrath of God. In an iconic moment from this event, Andre Spitzer was clubbed in the face on international television with an AK-47. In the end its three perpetrators were captured, but were released before trial in exchange for a hijacked Lufthansa jet. Because of poor planning and insufficient training, all eleven hostages were killed in addition to eight terrorists.  For 10 points, name this event in which members of Black September took Israeli hostages in a West German city during the 1972 Olympic Games.
Georg Sieber predicted this event, but was ignored because his scenarios were deemed preposterous.
Munich Massacre [or 1972 Munich Summer Olympics hostage crisis]