Boston marathon blasts happened without warning

We will turn every rock over to find the people who were responsible for this," Boston Police Commissioner Edward F. Davis said, according to Boston Globe.

Deadly Boston marathon horror is `potential` terrorism

Two bomb blasts which brought carnage to the Boston marathon with three dead and more than 100 injured was being treated Tuesday as a "potential terrorist" attack.

Boston marathon blasts: Hunt on for clues, apartment searched

A decade after the deadly 9/11 attacks, terror returned to haunt America when twin explosions near Boston marathon finish line, killed three and injured over 144.