But amid the horrific details of violence, stories of heroism have begun to emerge.
An eight-year-old boy told a local television affiliate how a teacher saved his life.
"I saw some of the bullets going down the hall that I was right next to and then a teacher pulled me into her classroom," he said. "It sounded like someone was kicking a door."
The child's grateful mother said the teacher "definitely saved" her son and another child.
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