Sounds as if the pipe bombs and other explosives were put in place the night/early morning before and most likely removed shortly after. I'm sure the good guys had intel and/or were watching the sounding area like hawks... I defer to the former tho... and I think this will play out on a grander scale. The surveillance Trump has secretly had in place since he took office, he's no dummy, he probably had real-time info about Russia collusion and all the parties involved. Spy Vs. Spy from the jump. General Flynn probably plays a large roll in all of this too. And the reason they had all communication and a heads-up on the pipe bombs or something even more sinister planned for the 6th. "They" wanted casualties and their plan got put out with a fire hose.