To play the media you will need to either update your browser to a recent version or update your Flash plugin.
The grisly spree of violence that began at the Boston Marathon this week also left a police officer dead. Law enforcement officials say the bombing suspects managed to shoot two officers as police were closing in on them. One, a transit police officer Richard Donohue, is in critical condition at Mount Auburn Hospital. The other, Sean Collier of the MIT campus police, was pronounced dead Thursday night.