ST. LOUIS (KSDK) - We are still trying to come to grips with what happened at the Boston Marathon on Monday.
The Marathon is one of America's greatest sporting events and that's what makes yesterdays deadly bombing even more frightening, because sporting events are our refuge.
PHOTOS:Boston Marathon explosions
But tens of thousands of people come together at sporting events, and we've all known they could be a target.
On Tuesday, NewsChannel 5's Mike Bush talked about that with NBC's Bob Costas.
Click the video player above to hear Costas' thoughts.