The police explained what was the probable cause of the bloody conflict at the Krasnodar school.
The incident occurred the day before at a branch of school No. 94, which is located in the village of Rossiysky.
Initially, it was claimed that the brawl broke out because an 8th-grade student asked his peers, who were listening to rap, to turn down the music.
But now it has become clear that one of the students was involved in the conflict, RIA Novosti reports, citing law enforcement agencies.
A total of 5 children were injured: three were seriously wounded, two escaped with minor injuries.
Among the victims are two teenagers who are brothers. They tried to stand up for a girl who was being bullied by the schoolboy who attacked them.
This provoked aggression in the boy, who took out a knife and used it against his peers.
The teenager was unable to escape and was detained at the scene.
Law enforcement officers opened two criminal cases on hooliganism and negligence.