A teacher wounded during shootings on Friday at two schools in Brazil succumbed to her injuries on Saturday, raising the death toll to four, said officials.

The attack by a teenage shooter who wore Nazi symbols has left about 10 people injured — including three teachers and a student, who are in critical condition — according to authorities in the city of Aracruz, in Espirito Santo state.

"Unfortunately, the tragedy of Aracruz has not yet ended," said state Governor Renato Casagrande in a tweet on Saturday.

He added, "With deep regret we confirm the death of another victim, teacher Flavia Amboss Mercon."

After Friday's shooting attack, Casagrande had declared three days of mourning in Espirito Santo.

The shooter has been identified as a former student at one of the public schools he targeted and ended up killing two people and injuring nine others.

Carrying a semiautomatic pistol and a revolver, he then went to another school that is located on the same street.

The Espirito Santo police said that he had been arrested and will face charges of murder.

The probe is still in the preliminary phase so the motives behind the attack are still uncertain, said investigators.

Latest shooting spurs calls for gun policy reform

School shootings have increased in Brazil in recent years. Friday's shooting at the two schools in Espirito Santo was the 12th such incident in the country since 2002, according to the research institute Sou da Paz.

The latest attack has evoked criticism around Brazil's gun-control laws, with critics hitting out at presidential orders relaxing regulations on firearms under far-right President Jair Bolsonaro, who has been a vocal supporter of gun rights.

According to experts, more than 40 decrees were facilitating purchases and registrations of weapons for Brazilians.

Everyday, people in Brazil are buying over a thousand weapons, according to Sou da Paz Institute.

mf/sri (AP, AFP)