what is kosta attack

A Kosta attack refers to a school shooting that occurred in Belgrade, Serbia on May 3, 2023. A 13-year-old student named Kosta Kecmanović opened fire in his school, killing eight children and a security guard, and injuring six children and a teacher. Kecmanović had been planning the attack for a month and had made a list of children he planned to kill and their classes.