FBI Presser (Finally) on Boston Bombings: See Video

I'm live-blogging below.  It was canceled twice yesterday amid rumors that suspects they were about to finger turned out bogus.

Starts 5:20 p.m.   Opens with revelation that they did develop "single person of interest" yesterday.  Then developed second--and show several photos.  Including guy with white baseball cap turned around.  And other young guy with black backpack that was set down.  And show bit of video.  Ask public for help but ask that people stay away, as these two may be "armed and dangerous."  Both men appear pretty young and not "dark-skinned."  CNN then says FBI site already crashing.   Guy's dark cap has distinctive markings--and Reddit seems to have IDed it--but easy to ditch.  Possibly white cap, too.  Someone on Twitter says they have been "bro-filed."  Here is video.