article_snippet.sent: Three people were killed and  
article_snippet.sent: 260 others injured in the attacks on April 15, 2013 .
article_snippet.sent: Among those who have come out against the death penalty are Bill and Denise Richard, whose eight-year-old son Martin was killed and seven-year-old daughter, Jane, lost a leg in the blasts.
article_snippet.sent: 26-year-old brother, Tamerlan, who died four days later after the pair shot dead a police officer.