youtube .com/ watch?v= oeG7ZY4zthw
This happened in 2013. The shooter was Alexandre Esteves and he was waiting on the staircase of Werneck high school for a boy who was bothering him. The boy was hit in the back but survived.
According to Lieutenant Rodrigo Lima Ferreira, the suspect had been suffering agressions: "He has special needs, he was suffering aggressions and the students also calling him fat at school".