The suspect, a 14-year-old student at the Vladislav Ribnikar school, was arrested after allegedly using his father's gun in the attack. An investigation into the incident is ongoing.
The school is located in the central Vracar neighborhood, and the police immediately cordoned off the area after the incident.
Local media published images of the suspect being led away in handcuffs by the police.
Serbia has strict gun laws, and mass shootings are rare, but the country has one of the highest rates of gun ownership in Europe due to the widespread availability of illegal firearms in the region.
An estimated 39.1 firearms per 100 people were recorded in Serbia in 2019, the third-highest in the world after the US and Montenegro. (ILKHA)