Stories say that they started tracking this guy 24-36 hours ago, per news reports this early morning, so they honed in on the guy.
Way to go FBI; APD and even, the ATF is involved...
If one pulls some idiotic stunt like this, this shows, you shouldn't use your cell phone though folks told me, through settings, you can turn tracking off. Criminals always make a mistake.
Also, the Fed Ex documents helped.
He was under surveillance at a hotel room, he had a bomb, so he was likely planning another hit.