The violence targeted both students and staff at the Tasso da Silveira public school located in Rio’s western neighborhood, Realengo.
Brazilian fire department spokesman Colonel Evandro Bezerra said on Thursday that “the number of fatalities is 13, and some 22 wounded, including gunshot wounds to the head,” AFP reported.
The wounded, some in critical condition, were rushed to a nearby hospital.
Reports say the shooter shot himself after opening fire on the children. Rio police also found a letter in the killer’s pocket saying that he wanted to kill himself.
The gunman was later identified as Wellington Menezes de Oliveira, 24, allegedly a former student at the school.