At least nine people were killed at a Brazilian primary school after two teenage boys entered the building and opened fire.

Among the dead were five schoolchildren, one adult who worked at the building, one person who was standing just outside the school and the two adolescent shooters, police said.

At least 17 other people, mostly children, were also shot at the Raul Brasil primary school on Wednesday and taken to hospitals, police said in a written statement.

The state of their health was not immediately known.

Police said the two teenagers wearing face masks entered the building and started shooting at about 9.30am local time on Wednesday.

The pair eventually shot and killed themselves.

Another shooting took place about 500 metres from the Raul Brasil school shortly before the killings at the school, but it was not yet clear if the two incidents were related.

About 1000 children attend the school, police said.

School shootings are rare in Brazil, even though the country is one of the world’s most violent, with more annual homicides than any other.

The last major school shooting was in 2011, when 12 children were shot dead by a former pupil in Rio de Janeiro.

Gun laws are extremely strict in Brazil, but it is not difficult to illegally purchase a weapon.