A gunman shot four people dead at a cathedral in Brazil before turning a firearm on himself while by the altar.
The killing happened just after mass at the Metropolitan Cathedral in Campinas, with four elderly people injured in the tragedy.
Hamilton Caviola Filho, a police investigator, said authorities had reviewed surveillance footage from inside the cathedral.
He told G1 news portal the shooter "came into the church, sat on a chair, with time to think, and then got up and starting shooting”.
Police identified the shooter as Euler Fernando Gandolfo, a 49-year-old systems analyst with no criminal record.
Globo News reported the man entered the front of the church and began shooting from two handguns.
"It was frightful," witness Alexandre Moraes told the GloboNews channel.
"He entered and shot randomly at people. They were all praying.”
Pedro Rodrigues, a 66-year-old retiree, said: "I suddenly saw a man stand up, take position in front of a couple and shoot them point blank. I ran out fast and he continued firing, many shots."
Wilson Cassante, a spokesman for the Campinas archdiocese, said church officials did not recognise the shooter or have any clue as to his motive.
"It's so sad," he said. "It's hard to imagine the pain this has caused."
The investigator also said that before shooting himself in the head, Gandolfo took a bullet in the ribs from responding police.
According to authorities, the suspect fired at least 20 shots, using just one gun despite having two with him.
Images from Globo News showed paramedics taking bodies and injured from the church.
Brazil had nearly 64,000 murders last year more than any other country, according to the United Nations.
Despite this, random mass shootings are relatively rare in the country.
