Thanks to our sponsors:

View all sponsors

Boston Bombing Investigation

The FBI says it will go to "the ends of the Earth" to find those responsible for the Boston Marathon bombing. We hear from security and terrorism experts on what clues we know so far, and how agencies plan for similar attacks on Chicago Tonight at 7:00 pm.

- Web-Exclusive: Local Marathon Runners React to Boston Bombings

Are you concerned about security in Chicago in light of the Boston bombings? Post your comments below or sound off on our discussion board.