Boston Bombing Day 2 | How Authorities Found the Bombers in the Crowd

Authorities scour surveillance videos for clues leading to the identities of the Boston bombers. Day 1: http://bit.ly/1TldQIe Day 3: http://bit.ly/1Tle9TB [This is the second of five installments of an ABC News digital special report '5 Days', which tells the hour-by-hour, day-by-day story of the investigation into the 2013 Boston Marathon bombing, with behind-the-scenes details based on interviews and evidence gathered by the FBI and Boston law enforcement .] SUBSCRIBE to ABC NEWS:    / abcnews   Watch More on http://abcnews.go.com/ LIKE ABC News on FACEBOOK   / abcnews   FOLLOW ABC News on TWITTER:   / abc   GOOD MORNING AMERICA'S HOMEPAGE: https://gma.yahoo.com/