campus monitor who responded immediately when there were signs of trouble in the school. unfortunately, those two heros gave their lives for our kids. reporter: an assistant football coach reportedly threw himself in front of children to block them from the bullets, saving countless lives, but losing his own. armed with only cell phones, students recorded dramatic video as a massacre unfolded. evacuations took place. i need everybody down! reporter: many trying to cope with what they saw. i ve heard a young man crying for his mother as he was dying. reporter: and the shocking loss of those they ll never see again. i saw at the beginning this was just it was all a drill, just a drill, until i saw my teacher dead on the floor. reporter: now a local white supremist group has ties to the 19-year-old who carried out the attack, a spokesman for the group told the antidefamation