At least six students and two teachers have died after hooded teenagers opened fire at a school in southern Brazil.
According to local authorities the youths, identified as former students, took their own lives shortly after their shooting spree.
Wednesday's shooting happened in a public school in Suzano, a suburb of Sao Paulo, Brazil's largest city.
The state government of Sao Paulo Joao Doria said two youths armed with guns and wearing hoods entered the school and began shooting at students and then killed themselves.
Speaking a few blocks from the public school in Suzano, Mr Doria said: "The school is on lockdown."
The age of the attackers was estimated to be between 20 and 25 years old, and authorities don't believe they were former students, the governor said.
He added that the school had been evacuated and police were inspecting possible explosives left by the shooters.
Students gathered outside the school recounted harrowing attacks and seeing several bodies lying in pools of blood.
"We were at recess and eating like normal and we heard three pops, then we tried to run to jump over the walls," Rosni Marcelo Grotliwed, a 15-year-old student, told Brazillian media outlet G1 news portal.
She said the attackers had guns and knives, and when she ran to the principal's office, she saw many dead people.
"My friend was stabbed in the shoulder and my other friend was shot," she said.
"I escaped with one friend and went home and then came back to look for another friend."
Horacio Pereira Nunes, a retiree whose house is next to the school, said he began hearing shots around 10 a.m.
"Then a lot of kids started running out, all screaming," he said. "It didn't take long until police arrived."
The public school, Raul Brasil Professor, has more than 1,600 students from elementary to high school grades, teachers gathered outside said.
Latin America's largest nation has the largest number of annual homicides in the world, but school shootings are rare.
Brazil's new President Jair Bolsonaro recently announced that gun ownership controls would be loosened.