Thanks for the additional info.
Had not heard about the call from the FBI on Thursday.
Does this mean they were more aware than they have admitted of his potential and the danger? Does it mean he was in fact actively monitored?
Or does it mean they (or NSA) heard some tidbit of his cell phone or internet traffic? (sounds more likely)
I doubt it. I believe the FBI has stated they didn't learn the identities until shortly after the Watertown shootout.
To me, the report (if true) confirms that the FBI was not yet onto him, that they still considered him of peripheral interest, as somebody to be ruled out as a matter of due diligence. If they had considered him a serious suspect, I'm sure they would have shown up in force at 410 Norfolk Street and pulled him in.
The FBI's Thursday press conference was a good move. It smoked 'em out. Even though the released photos and videos didn't show the faces well enough for identification, the brothers had to know the game was up. Better photos would be found (they were, by early Friday morning). Or somebody would recognize them and report them. So, they made their chaotic getaway attempt, in which MIT Officer Sean Collier was killed.