On Sept. 5, 1972, the most brazen and infamous act of terrorism at a sporting event took place when Palestinian terrorists murdered 11 Israeli athletes at the 1972 Olympics in Munich.
Gunmen belonging to the militant group Black September raided the Olympic Village where the athletes resided, and stormed two apartments in which Israeli Olympians were relaxing away from the field. The attack played out on television screens as images of masked men bearing guns were beamed to millions around the globe.
In the wake of the tragedy, competition was suspended, and a service was held for the fallen athletes.
Since the events of the 1972 Olympics, security has been considerably increased and has become a primary concern of event organizers. For the 2012 Olympics in London, security spending topped $1.6 billion.