The FBI is investigating the possibility that a power outage on the last day of the Winter Olympics was caused by a bomb, The Associated Press has learned. Electricity was cut to 33,000 customers — including the airport and the main media center downtown — for up to two hours Sunday morning when a circuit breaker exploded at a substation. Investigators later found that a security fence had been cut. A law enforcement source who spoke on condition of anonymity said railroad spikes found at the scene had caused clear indentations in metal near the site of the explosion. The source said those marks were one of the factors that led investigators to consider the possibility of a bomb. Full Story