Eight teenagers and a guard were killed early Wednesday after a boy opened fire at a school in central Belgrade, according to a statement by the Ministry of Internal Affairs. Another six pupils and a teacher were injured in the attack and have been taken to hospital, the ministry said in a statement. It is unclear whether the teenagers died at the scene or while they were being treated in the capital's emergency center. The guard was killed while trying to stop the shooter. Police identified the shooter by his initials, KK. The statement said he was a student at the school and was born in 2009. He was arrested in the school, police said. Police said they had received a call about the shooting in the Vladislav Ribnikar school in Belgrade's central Vracar neighborhood at around 8.40 am local time. The boy apparently fired several shots from his father's gun at other students and the school guard. 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. Officers in helmets and bulletproof vests cordoned off the area around the school shortly after 08:40 local time (07:40 GMT). An investigation into the motives behind the incident is underway. Reports said terrified parents have arrived at the school trying to find their children. "I saw kids running out from the school, screaming. Parents came, they were in panic. Later I heard three shots," one student told the Serbian state broadcaster RTS. Milan Milosevic, the father of one of the pupils at the school, said his daughter was in the class where the gun was fired and managed to escape. "[The boy] first shot the teacher and then he started shooting randomly," Milosevic told broadcaster N1. "I saw the security guard lying under the table. I saw two girls with blood on their shirts. They say he [the shooter] was quiet and a good pupil. He recently joined their class." Milan Nedeljkovic, mayor of the central Vracar district where the school is located, said doctors were fighting to save the teacher's life. Mass shootings are comparatively rare in Serbia, which has very strict gun laws, but gun ownership in the country is among the highest in Europe. The western Balkans are awash with hundreds of thousands of illegal weapons following wars and unrest in the 1990s. In 2019, it was estimated that there are 39.1 firearms per 100 people in Serbia. — Agencies