A 13-year-old student Kosta, now among the youngest mass murderers in the world, but with the largest number of victims, killed nine students and a school guard at Vladislav Ribnikar elementary school in Belgrade. He wounded five more.
Overview：A 13-year-old student Kosta, now among the youngest mass murderers in the world, but with the largest number of victims, killed nine students and a school guard at Vladislav Ribnikar elementary school in Belgrade. He wounded five more.
