WASHINGTON — Super Bowl 50 will be one of the most highly guarded sporting events in U.S. history as security services pile resources into preventing any repeat of the deadly attacks in Paris and San Bernardino, although officials have said there is no specific or credible threat to Sunday's game in the San Francisco Bay Area.
November's attacks in the French capital by gunmen linked to the Islamic State militant group included suicide bombings near entrances to the national stadium as a soccer game was underway, provoking fears of attacks targeting crowds attending big sporting events elsewhere.