Demonstrators vandalised public buildings and lit fires in Brazil’s largest city Saturday in protest at the cost of staging this year’s World Cup, reports Xinhua.
Local media reported that the rally began peacefully before being infiltrated by the Black Bloc anarchist group.
Police were forced to use stun grenades and tear gas to disperse the crowds.
Sao Paulo’s secretariat of public security said the detained protesters were released Sunday after a night in custody.
According to military police, seven people were wounded during the protest, including five police officers.
Anti-government demonstrations that began during last year’s Confederations Cup have become a regular occurrence in Brazil’s major cities.
Many Brazilians have expressed their anger that billions of dollars are being spent on the World Cup instead of essential services like hospitals, education and transport.