article_snippet: More than 260 others were maimed or injured by two pressure cooker bombs that exploded within 12 seconds of each other.
article_snippet: the second bomb blew large holes into the boy's chest and organs -- "tore large chunks of flesh out of Martin's body," U.S. prosecutor Bill Weinreb said.
highlights_snippet: Bomb "tore large chunks of flesh out" of boy's body, prosecutor says .
  