FBI The FBI has released these photos of two suspects in the Boston Marathon bombing. FBI releases surveillance video taken on the day of the Boston Marathon blasts which they say shows persons of interest linked to the attack By Pete Williams, Erin McClam and Tracy Connor, NBC News The FBI has released video and photos of two "armed and extremely dangerous" suspects in the Boston Marathon bombing and appealed for the public's help in identifying them. The images show two men in baseball caps who were seen walking together through the crowd. One of them was seen putting down a black backpack at the site of the second blast in Monday's attack, minutes before an explosion. "Somebody out there knows these individuals'�though it may be difficult, the nation is counting on those with information to come forward and provide it to us,' Boston FBI Special Agent in Charge Richard DesLauriers said at a Thursday briefing. "We consider them to be armed...