Eight pupils and a security guard were killed when a boy opened fired in a Belgrade elementary school on Wednesday morning, news agency Tanjug reported, quoting a source in the interior ministry.
Earlier, media had reported that a security guard was killed and five children had been injured.
One teacher was also injured and is receiving emergency treatment, Tanjug reported.
(Reporting by Aleksandar Vasovic and Ivana Sekularac; Editing by Gareth Jones)