The boy, Matheus Santos Moraes, was struck by a bullet on Saturday. Police say he was hit in crossfire during a confrontation with drug traffickers, Globo reported yesterday.
The public safety chief for the Mage area on the northeastern outskirts of Rio de Janeiro called the ensuing violence unprecedented "chaos."
"Mage went through a situation never seen before in the municipality," the official, Nelson Vinagre, told Globo on Sunday. "We had 12 buses set on fire and several businesses looted."
The boy's mother, Patricia Moraes, denied that there had been an exchange of gunfire at the time her son was killed.
"I saw the police shooting. When I went to get him, he had already fallen," she said.
Police said they were investigating the tragedy.
