BELGRADE, Serbia—A 13-year-old who opened fire Wednesday at his school in Serbia’s capital drew sketches of classrooms and made a list of people he intended to target in a meticulously planned attack, police said. He killed eight fellow students and a guard before being arrested.
The shooter first killed a guard at the school in central Belgrade and then three students in a hallway, according to senior police official Veselin Milic. He then entered a history classroom—apparently choosing it simply because it was close to the entrance—and opened fire again, Milic said.
The assailant called police himself when the attack was over, though authorities received a call reporting the shooting two minutes earlier….