Boston police say two blasts near the finish line of the Boston Marathon killed two people and injured many others.

Police Commissioner Edward Davis says a third explosion at the JFK Library may be related to the other blasts.

David says there are no injuries stemming from the third explosion.

He urged people to stay indoors and not congregate in large groups.

Spokane nearly had a similar incident.  Back in January of 2011, Kevin Harpham tried to detonate a bomb during the Martin Luther King Unity March.  Two alert INB Performing Arts employees noticed the backpack before it went off and alerted authorities, averting disaster.

Do today's blasts in Boston make you re-think taking part in large scale events like Bloomsday and Hoopfest?