Two men have been arrested near Sao Paulo on charges of torturing the 17-year-old. They confessed to the attack, saying they had caught him about to steal a bike from a disabled man, Brazilian media reported Monday.
The victim's family became concerned when he went missing on May 31 and then were horrified to find a video of him posted online undergoing the tattooing.
In the footage, which was widely shared on social media, the victim is seen sitting while a man uses a tattoo machine to mark his forehead in large, crudely dawn capital letters.
"They committed a cowardly and cruel act of extreme brutality torturing this adolescent," said Ariel de Castro Alves, with the state human rights commission Condepe on Globo news site. "Before tattooing, they tied his hands and feet. He was begging for mercy."
The victim, who spoke to Globo with his back to the camera, denied he had been stealing. "I was drunk and I bumped into the bicycle and it fell over," he said.
When the tattooing started "I wanted to die," he said.
His torturers photographed him immediately after but when he tried to cover up the tattoo with his fringe, "they cut off my hair," he added in the report, where he appears with his head shaved.
Brazil is one of the world's most violent countries, with nearly 60,000 murders a year, according to the latest available statistics for 2015. That's about 161 homicides a day, with a per capita homicide rate three times above the UN threshold for "endemic violence."
Confronted by rampant crime and an often inefficient police force, vigilante violence against criminal suspects is widespread. This commonly includes beatings of suspected muggers by bystanders and even public executions by mobs -- frequently captured on cellphone footage.
Family lawyer Leonardo Rodrigues urged Brazilians not to jump to conclusions about the teen after seeing him accused of being a thief.
"Many people shared the image of him and made judgments without knowing the facts. He did not do anything that was said and spread on the internet," Rodrigues said.
An online campaign to raise money to help the adolescent's recovery had already surpassed its target of 15,000 reais ($4,520)after two days.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
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