Boy , 1999 , arrested after deadly attack at secondary school in Barcelona . The teenager allegedly shot and killed a teacher using a crossbow . Teen had written a 'kill list ' of 25 teachers and students , classmates say . Two students and two teachers were injured in the attack this morning . Attack took place on 16th anniversary of Columbine school massacre .
Boy , 13 , arrested after deadly attack at secondary school in Barcelona . The teenager allegedly shot and killed a teacher using a crossbow . Teen had written a 'kill list ' of 25 teachers and students , classmates say . Two students and two teachers were injured in the attack this morning . Attack took place on 16th anniversary of Columbine school massacre .