the plot concerned mumbai-style command attacks in europe on symbols of economic power like banks and stock exchanges. the potential perpetrator, sources say, are people with western passports that can travel around europe. the intelligence is not precise. but the believe is that a dozen individuals may be involved. on the record, u.s. officials are saying as little as they can about the investigation. we are not going to comment on specific intelligence. as doing so threatens to undermine intelligence operations that are critical and protecting the united states and our allies. on background, u.s. officials say they see no indication that the intelligence about potential terror attacks in europe has a u.s. dimension. but, they are continuing to look. they don t know what they don t. they don t know they only have pieces of this puzzle.