Brazil: Clashes in Rio Slum Over Death of Youth Police officers investigating the death of a teenager clashed with residents of a Rio de Janeiro slum, police said Wednesday as Brazilians staged a series of protests on issues ranging from alleged police brutality to low wages. Rio police said in a statement that three buses were burned and a police car damaged in Tuesday night's clash in the sprawling Penha slum. Police were called in to investigate the death of a 17-year-old boy, whose body was found in the neighborhood. "As the military police approached, a group of locals began a violent protest," the statement said. The teen, whose name was not released, went missing Monday. His body showed no bullet wounds, and the cause of death was not immediately clear, police said. News reports suggested the protesters suspected the youth died in a confrontation with police. Police killings are not unusual in Rio, where officers are sometimes linked to armed militias. A demonstration was called for Wednesday in another Rio slum, Rocinha, to call for light to be shed on the disappearance of a local bricklayer who was last seen in police custody. The protest came on the one-month anniversary of the disappearance of Amarildo de Souza, a 42-year-old father of six who was hauled into a Rocinha police station for questioning July 14. Police have said he was released shortly after, but video surveillance shows no trace of Souza after he entered the police station. His family and supporters say they suspect he was killed by police and his body dumped in a clandestine graveyard. Souza's disappearance has become a hot-button issue in Rio, particularly among slum dwellers and critics of Rio de Janeiro state Gov. Sergio Cabral. Cabral has been the target of protests since June, when a wave of mass demonstrations against government corruption and calling for improved public services swept Brazil. Protesters allege Cabral is corrupt and want an investigation into spending on projects linked to next year's World Cup and the 2016 Olympics, which Brazil is hosting. A demonstration was scheduled outside the Guanabara Palace later Wednesday. Several thousand mostly university professors also marched through central Rio on Wednesday demanding higher pay and better working conditions, while people calling for improved legislation for the disabled staged a protest in the capital, Brasilia. In Sao Paulo, Brazil's biggest city, thousands of demonstrators protested against an alleged price-fixing cartel involved in the construction and upkeep of the subway and train systems of the cities of Sao Paulo and Brasilia.