Due to the World War I & II three Olympic Games cancelled in 1916, 1940 and 1944. Terrorism affected the games in 1972, in Germany when Israeli Olympic team was hostage by the Palestinian terrorist group and killed all of them. This black September is also known as the Munich Massacre in Olympic history. In addition to this in 1996, Atlanta Olympic a bomb was detonated in the Centennial Olympic Park that killed two people. These terrorist attacks make the security a major concern for Olympic Games and plan accordingly to avoid such thing again.