Security camera footage showed the assailant wearing a bulletproof vest and using a semiautomatic pistol for the attacks, Espirito Santo public security secretary Márcio Celante said in a video provided by the secretariat’s press office.
In addition to the fatalities, 11 people were wounded, including nine instructors, said Celante, who noted that in the public school the shooter gained access to the teachers lounge after breaking a lock.
The shooter covered his face, making it difficult to identify him, Celante said, adding that police are investigating whether he was helped by others.
School shootings are uncommon in Brazil, but have happened with somewhat greater frequency in recent years.
In a video posted to social media, Espirito Santo Gov. Renato Casagrande said he is monitoring the situation and has sent authorities to investigate.