Brazil's CUT labor federation - the country's largest - and members of social movements are holding protests Monday in this metropolis against a controversial pension overhaul bill, a measure that has been stalled for months in Congress.
Several unionists blocked the main bus terminals in three cities of the Sao Paulo metropolitan region - Guarulhos, Santo Andre and Sao Bernardo do Campo, although the flow of vehicles resumed after a few hours.
Other demonstrators caused massive traffic jams when they used burning tires to set up a barricade on the Dutra highway, a main road that links Brazil's largest city with Rio de Janeiro.
The CUT said in a statement that the protests were called to pressure Congress to permanently shelve the pension bill, which is part of conservative President Michel Temer's austerity drive.
Temer's administration already has successfully pushed for a spending cap that limits public spending to inflation for the next 20 years. He also plans to sell the government's stake in dozens of assets - including Eletrobras, Latin America's largest power utility - as part of a plan to get Brazil's fiscal house in order.
The proposed pension overhaul, which would require changes to the constitution, has undergone different changes since Temer's administration introduced it last year.
The president, however, has struggled to rally support for the bill among legislators in his own ruling coalition, many of whom are wary that supporting it could cost them in the October general elections.
Despite some changes that have watered down the bill, unions remain angry over one provision that would set the minimum retirement age for men and women at 65 years and 62 years, respectively.
Under current law, men can retire after contributing to the pension system for 35 years and women can do so after 30 years of contributions, irrespective of their age.
A vote on the pension measure that had been scheduled for this month in Brazil's lower house of Congress may be delayed after Temer signed an emergency decree Friday giving the army control of public security in Rio de Janeiro.
Under Brazilian law, Congress cannot approve changes to the constitution while a federal intervention is in force.