On Saturday, the death toll from twin school shootings in Brazil increased to four after a teacher who was wounded in the attack by 16-year-old wearing Nazi emblems succumbed to her wounds, according to officials.

Authorities in the city of Aracruz, in the state of Espirito Santo, reported that some of the approximately 10 wounded, including three teachers and a student, were in critical condition following the attack on Friday that shook the country, which has seen an increase in school shootings in recent years.

"Unfortunately, the tragedy of Aracruz has not yet ended," stated Renato Casagrande, the governor of the state on Saturday.

"With profound sorrow, we confirm the passing of another victim, teacher Flavia Amboss Mercon," tweeted the governor of Espirito Santo, who had announced three days of mourning in the state.

The attacker was a former student at the public school he initially targeted when he shot and killed two teachers and injured nine others. He then went to a nearby private school, where he killed a teenage girl and injured numerous others.

Police in Espirito Santo reported that he has been apprehended and will be charged with murder and attempted aggravated murder.

Saturday funerals were held for the last three victims, according to Brazilian media.

"My daughter has always been joyful and loving. Thais Sagrillo, the mother of a 12-year-old girl who was murdered, told Globonews, "I lost my daughter to hatred."

The incident was the thirteenth school shooting in Brazil since 2002, according to the Sou da Paz research institute.

Critics criticized a series of presidential decrees issued by far-right President Jair Bolsonaro that relaxed limitations on firearms and ammunition in response to the most recent incidents.

Bolsonaro was defeated in last month's elections by Luiz Inacio Lula da Silva, who has been very critical of the ex-army captain's easing of gun-control legislation.

Officials reported that the shooter, the son of a police officer, used two handguns registered to his father, one of which was the officer's service firearm and the other a privately registered weapon.

Casagrande stated that the youngster looked to have meticulously planned the attack.

The shooter entered the school wearing military-style camouflage and wielding a gun, as captured by surveillance cameras and broadcast by Brazilian media.

Investigators reported that he wore a swastika on his fatigues and were investigating whether he had ties to extremist organizations.