Police say a teenage boy opened fire in a school in central Belgrade, killing eight children and a school guard.
Six more children and a teacher were hospitalised after Kosta Kecmanovic, a 13-year-old student at the Vladislav Ribnikar school, launched the shooting, police in Serbia said.
The teen drew sketches of classrooms and wrote a list of people he intended to target in a meticulously planned attack, according to officers.
The teen first killed a guard and three students in the hallway before entering the nearest classroom where he opened fire again, senior police official Veselin Milic said.
The assailant called police himself when the attack was over, though authorities had already been alerted to the shooting, and he was arrested in the schoolyard.
Police also said he used his father’s handgun, which was licensed.
Interior Minister Bratislav Gasic said the gun was kept in a safe but the teen apparently knew the code. His father was also arrested.
Reports said terrified parents arrived at the school trying to find their children.
Local 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.
Mass shootings in Serbia and in the wider Balkan region are extremely rare and none has been reported in schools in recent years.
In the last mass shooting, a Balkan war veteran in 2013 killed 13 people in a central Serbian village.
Experts, however, have repeatedly warned of the number of weapons left over in the country after the wars of the 1990s.
They also note that decades-long instability stemming from the conflicts as well as the ongoing economic hardship could trigger such outbursts.
Milan Milosevic, who said his daughter was in a history class when the shooting took place, told N1 television that he rushed out when he heard what had happened.
“I asked where is my child but no one could tell me anything at first,” he said. “Then she called and we found out she was out.”
“He (the boy who fired the gun) fired first at the teacher and then the children who ducked under the desks,” Mr Milosevic quoted his daughter as saying. “She said he was a quiet boy and a good student.”
Police sealed off the blocks around the school.
Two things immediately stood out about this mass shooting:
The other day, another mass shooting in Serbia happened again. Apparently the guy wore neo-nazi symbols so I wonder if Russia has anything to do with it