At least three people were killed and 11 wounded after a former student opened fire at two schools in the southeastern Brazilian state of Espirito Santo, police said.
The alleged shooter was identified as a 16-year-old who wore military-style camouflage attire with Nazi symbols, the authorities said of the twin attacks that took place at 10am (13:00 GMT) on Friday in the town of Aracruz, 80km north of state capital Vitoria.
He first fired on teachers at his former school, a public primary and secondary school, killing two people and injuring nine.
The shooter then went to a private school on the same street, where he killed an adolescent girl and wounded two people, officials said.
The teenager has been arrested, Espirito Santo Governor Renato Casagrande confirmed.
“He was a student at (the first) school until June, a 16-year-old minor. His family then transferred him to another school. We have information he was undergoing psychiatric treatment,” Casagrande told a press conference.
Two guns were used in the attack by the teenager, who is the son of a military police officer. Both firearms were registered to his father.
Security camera footage broadcast on Brazilian media showed the shooter running into the school, rushing down the corridors with a semi-automatic weapon and firing shots. Police are investigating any potential links to extremist groups as he had a swastika on his fatigues.
The lives of some of the injured remained at risk, the governor said, as he declared three days of mourning in the state.
School shootings are uncommon in Brazil, but have witnessed an uptick in recent years.