efe-epaRio de Janeiro

Events took place in each of Brazil's 27 states on Friday as a part of a general strike called by unions against right-wing President Jair Bolsonaro's plan to cut pensions, but the material impact of the mobilization varied widely by location and economic sector.

Roughly 45 million workers heeded the call to walk off the job, the unions said.

While many businesses were unaffected, most teachers joined the strike and public transportation was sharply curtailed in hundreds of municipalities in 19 states.

The morning hours saw isolated incidents surrounding protests.

In Niteroi, a suburb of Rio de Janeiro, a motorist drove his vehicle into a group of demonstrators, while militants in Sao Paulo - Latin America's largest city - set a car on fire to block a street, prompting police to respond with stun grenades.

As evening approached, thousands of people gathered in Sao Paulo's financial district for a peaceful protest that addressed not only the proposed pension reforms but other grievances, including the 2018 assassination of leftist Rio city councilor Marielle Franco, amid a general rejection of Bolsonaro.

"He is an incompetent," a history teacher who identified himself only as Gustavo said of the president. "I came to protest against the retirement reform and for better conditions in education. The reform is harmful for the entire working class and especially for teachers."

The crowd in Sao Paulo also demanded the release from prison of former two-term President Luiz Inacio Lula da Silva, whose 2017 conviction for corruption has been called into question with the publication of messages showing bias on the part of Judge Sergio Moro, who is now justice minister.

Here in Rio, the biggest concentration of protesters was around the Candelaria Church in the city center.

"This strike is very important because when we strike we show our dissatisfaction with the current government and, above all, with the withdrawal of rights. Brazil has a democracy of recent vintage that is now being threatened in various ways," 30-year-old attorney Ana Myriam said.

The event unfolded peacefully until around 7.00 pm, when police used stun grenades to disperse a large group of protesters.

Friday marked the unions' first direct challenge to Bolsonaro, whose tenure, which began Jan. 1, has been shaped by scandals and a seeming lack of coordination on the policy front.

To make matters worse, Latin America's No. 1 economy seems on the verge of falling into recession.

Brazilian gross domestic product (GDP) plunged nearly 7 percent in 2015-2016, but growth resumed in 2017, albeit at a modest annual rate of 1 percent.

After gaining 1 percent again last year, GDP inched up 0.5 percent in the first quarter of 2019 and more than 13 million Brazilians are unemployed.