The 17-year-old son of a police detective opened fire at a high school in Omaha, Nebraska Wednesday, killing his principal and forcing other students to take cover. The principal later died at the hospital, and, after being placed on lockdown, everyone else at the school emerged safe. The gunman fled and killed himself in his car about a mile away. He had recently transferred to the high school from another one near Lincoln, and left behind an expletive-filled Facebook rant saying that people would hear about the "evil" things he did and that his new school drove him to violence. People remember him as an outgoing, fun person who never seemed angry.