A gunman had shot dead almost 12 children at a school in the Brazilian city of Rio de Janeiro before he had killed himself, police reports.
Around 12 others had been wounded when the man had entered the school with two revolvers and had began shooting.
The killer was identified as a 23-year-old former pupil named Wellington Menezes de Oliveira.
President Dilma Rousseff wept as she had condemned the school massacre.
The attack had happened at the Escola Municipal Tasso da Silveira school.
Officials reported that Oliveira had arrived at the start of the school day and had got into the building by stating that he had came to give a lecture, but then went into a classroom and had began shooting.
Teachers had barricaded the doors of other classrooms while the children hid under their desks.
Some wounded children had escaped and then alerted the police, who had rushed to the scene.