The Department of Homeland Security is addressing the threat and has efforts under way to “ramp up security,” White House press secretary Scott McClellan said.
US officials do not have specific knowledge about where, when or how such an attack would take place, but the CIA, FBI and other agencies “are actively working to gain that knowledge,” Mr Ridge said.
When asked if the threat is considered higher at the political conventions this summer or as the nation gets closer to the presidential election in early November, the official said concerns are high from this point in time forward.
