The victims were mostly elderly people, who had remained at the church to pray after Mass had concluded. The 49-year-old attacker, who was not a member of the church, killed himself at the scene.
A gunman has killed four people after opening fire following a midday Mass in a Catholic cathedral in the Brazilian city of Campinas. The attacker later died at the scene after turning the gun on himself.
Worshipers at the Metropolitan Cathedral in Campinas, located some 60 miles (100 kilometers) north of Sao Paulo, were praying when the incident occurred. The gunman, whom police identified as 49-year-old Euler Fernando Gandolfo, entered the church and sat among them.
After some time, Gandolfo drew his gun and began shooting the people around him. Most of the worshipers were elderly people.
Police in the adjacent public square rushed into the house of worship upon hearing the shots, investigator Jose Henrique Ventura told reporters at the scene.
The gunman then ran toward the altar while firing his weapon back at police. He fell to the ground, wounded by police gunshots, and then shot himself in the head. The attack also left four worshipers wounded, though not critically.
"It's so sad," said Wilson Cassante, a press officer with the archdiocese. "It's hard to imagine the pain this has caused."
In the aftermath, police found two guns with 28 rounds left in Gandolfo's possession. Authorities said the shooter, a systems analyst with no criminal record, was not a member of the church.
Ventura told reporters that a backpack had been found with Gandolfo's identification, but it contained no suicide note or clues as to the motive. "Thanks to the intervention of police, something much bigger was avoided," Ventura said.
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President-elect Jair Bolsonaro took to Twitter to express solidarity with the victims. "We are following the authorities' investigation of the barbaric crime committed today in the Metropolitan Cathedral of Campinas, in Sao Paulo. Our solidarity is with the victims of this tragedy and their families," Bolsonaro wrote.
While Brazil had nearly 64,000 murders last year, more than any other country, mass shootings in public areas are relatively rare. But a rise in gun violence remains one of the most important issues for citizens in the South American nation.
Bolsonaro has vowed to loosen gun laws, to allow Brazilians to arm themselves against criminals, a policy that many critics have said could only lead to more violence.
jcg/cmk (EFE, AP, Reuters)