Eight children and a security guard were killed after a teenage boy opened fire at a school in the Serbian capital, Belgrade, on Wednesday, police said.
The suspect, a seventh grade student whom police identified as Kosta Kecmanović, was arrested in the school yard, authorities said. They said he had fired several shots from his father’s gun.
Veselin Milić, the head of Belgrade police later told a news conference that the shooting was “planned for a month.”
He added that Kecmanović did not provide a motive for an attack that also left six children and a teacher injured and hospitalized.
Milić also showed a list that he said was found in the suspect's apartment. On it he said, were the names of the students the suspect planned to kill, as well as a precise plan of the school with the entrances and exits marked.
It was unclear if he shot any of the people named on his list or how many rounds were fired.
Because he is under 14, he cannot face criminal charges, the Belgrade prosecutor’s office told The Associated Press. Social services will determine what happens to him, the AP reported.
Interior minister Bratislav Gasic said the weapons were licensed and kept in a safe, but the teenager, who had been to shooting ranges, apparently knew the code. The suspect's father was also arrested but has yet to be charged, police said.
Officers had responded to reports of a shooting at the Vladislav Ribnikar school around 8:40 a.m. local time Wednesday, police said in a separate statement.
Milan Milosevic, the father of one of the students at the elementary school, said his daughter “managed to escape” the shooting.
He told the broadcaster N1 that the suspect had "fired first at the teacher and then the children who ducked under the desks,” according to The AP. “She said he was a quiet boy and a good student,” he quoted his daughter as saying, according to the news agency.
Mass shootings in Serbia and the broader Balkan region are extremely rare, with none reported at schools in recent years.
"I really don’t know what to say. This is a complete tragedy of a society," Serbian politician Miodrag Gavrilovic said in a tweet reacting to the shooting. "Aggression and violence is at every turn, but if the shooting happens in an elementary school ... "
"I seriously fear for the consciousness of our children," the member of Parliament later wrote. "Well, that boy is only one year older than my son. I do not know. This tragedy deeply affected me personally."
Media footage from the scene showed commotion outside the school as police removed the suspect, whose head was covered as officers led him to a car parked in the street.