The Challenge Of Marathon Security

Boston Globe sports reporter Shira Springer was covering the Boston Marathon yesterday.

She also covered the London Olympics, where security was of prime concern.

She tells us about the security challenges posed by major sporting events like the Olympics, and the unique challenges at marathons, where people are carrying backpacks and runners' belongings.

London police will be reviewing security for the London Marathon on Sunday, but organizers say that the marathon will go on.