• Federal Agents Zero In on Bomb's Charred Remains     Wednesday, 17 Apr 2013 | 7:32 AM ET

    Bomb fragments are being reconstructed at an FBI laboratory, reports CNBC's Scott Cohn. And, Philip Mudd, New America Foundation, discusses the psychological impact of terrorism and how to avoid copycat attacks.

  • Congress Reacts to Ricin Letter & Boston Bombings     Wednesday, 17 Apr 2013 | 7:10 AM ET

    CNBC's Eamon Javers has the latest details on a ricin-tainted envelope sent to the office of Sen. Roger Wicker (R-MI). Sen. Jack Reed (D-RI) and Sen. Angus King (I-ME) discuss a poison-laced letter sent to Capitol Hill, as well the Boston Marathon bombings.

  • Poison Laced Letter Sent to US Senator     Wednesday, 17 Apr 2013 | 6:10 AM ET

    A ricin-tainted envelope was sent to the Capitol Hill office of Sen. Roger Wicker, (R-MI), reports CNBC's Eamon Javers.

  • CNBC's Scott Cohn reports the FBI and state and local law officials are intensifying their probe into Monday's bombing at the Boston Marathon, recovering two pressure cookers packed with nails and other metals.

  • Security Lockdown for Thatcher's Funeral     Wednesday, 17 Apr 2013 | 1:39 AM ET

    CNBC's Ross Westgate reports on the huge security operation ahead of the funeral of former UK Prime Minister Baroness Thatcher.

  • National Security in Washington Spotlight     Tuesday, 16 Apr 2013 | 1:45 PM ET

    The latest on the terror events in Boston and how the nation's capital is responding, with CNBC's Eamon Javers.

  • CNBC's Bertha Coombs has the latest details on reopening of Boston's airport, as law enforcement officials continue to collect video from surveillance cameras and watch for a man seen leaving the scene after the blast.

  • Large events around the globe are affected by the tragic events in Boston, reports CNBC's Tom Mackenzie.

  • The "sort of attack" we saw in Boston, feels like the kind of attacks we've been seeing in the past 10 years or more, said, Stewart Baker, Steptoe and Johnson partner. "We are going to find these folks, the Bureau is really good at dealing with this kind of evidence and crime scene," he added.