1 million anti-government protesters took to the streets in scores of cities, with clusters battling police and destroying swaths of storefronts and government buildings.
President Dilma Rousseff called an emergency meeting about the protest with top Cabinet members Friday, after a largely silent and much criticized response to some of the biggest demonstrations seen in this 192 million-person country in decades.
There were also growing calls on social media and in mass emails for a general strike next week. If it materializes, the action could bring in unions and other organized groups to what has so far been an amorphous explosion of discontent over everything from high crime to poor education.
Brazilian media have mercilessly called out Rousseff and other leaders for their confused response to the protests.
"Dilma Rousseff and (Brasilia Gov.) Agnelo Queiroz are the epitome of Brazilian rulers," wrote political commentator Fernando Rodrigues in the country's biggest newspaper, Folha de S. Paulo.
"They embody the perplexity and the lack of leadership capabilities of several parties' politicians vis-a-vis the new phenomena of protests without leaders or defined proposals. ... It seems they are just waiting and hoping the tsunami will end."
To be sure, the lack of any organization or concrete demands behind the protests has made a unified government response nearly impossible. Several cities have cancelled the transit fare hikes that had originally sparked the demonstrations a week ago, but the outrage has only grown more intense.
Gilberto Carvalho, the secretary general of the presidency, provided little direction Friday after a meeting to discuss Pope Francis' planned July visit to Rio de Janeiro for World Youth Day.
"We can't anticipate the future," Carvalho said. "We don't know what it's going to be like. Perhaps things will not be so intense (as the recent protests) but we have to be prepared for anything."
Foreign Minister Antonio Patriota, for one, hit back at protesters the morning after his modernist ministry building was attacked by a boisterous crowd. At one point, smoke billowed from the building, and windows were shattered along its perimeter.
Standing before the battered ministry, he told reporters Friday he "was very angry" that protesters attacked a structure "that represents the search for understanding through dialogue." Patriota called for protesters "to convey their demands peacefully"
"I believe that the great majority of the protesters are not taking part in this violence and are instead looking to improve Brazil's democracy via legitimate forms of protest," Patriota said.
The majority of protesters have been peaceful, and crowds have taken to chanting "No violence! No violence!" when small groups have prepared to burn and smash. The more violent demonstrators have taken over once night has fallen.
Protesters and police clashed in several cities into the early hours Friday.
At least one protester was killed in Sao Paulo state Friday when a driver apparently became enraged about being unable to travel along a street and rammed his car into a group of demonstrators.
In Rio de Janeiro, where an estimated 300,000 demonstrators poured into the seaside city's center, running clashes played out between riot police and clusters of mostly young men with T-shirts wrapped around their faces. But peaceful protesters were also caught up in the fray, too, as police fired tear gas canisters into their midst and at times indiscriminately used pepper spray.
Thundering booms echoed off stately colonial buildings as rubber bullets and gas were fired at fleeing crowds.
At least 40 people were injured in Rio, including protesters such as Michele Menezes, a wisp of a woman whose youthful face and braces belied her 26 years. Bleeding and with her hair singed from the explosion of a tear gas canister, she said she and others took refuge from the violence in an open bar, only to have a police officer toss the canister inside.
The blast ripped through Menezes' jeans, tearing two coin-sized holes on the back of her thighs, and peppered her upper arm with a rash of small holes.
"I was leaving a peaceful protest and it's not the thugs that attack me but the police themselves," said Menezes, removing her wire-rim glasses to wipe her bloodshot eyes.
She later took refuge in a hotel, along with about two dozen youths, families and others who said they had been repeatedly hit with pepper spray by motorcycle police as they also sheltered inside a bar.
Protesters said they would not back down.
"I saw some pretty scary things, but they're not going to shake me. There's another march on the 22nd and I'm going to be there," said 19-year-old university student Fernanda Szuster.
Asked if her parents knew she was joining in the protests, Szuster said: "They know and they're proud. They also protested when they were young. So they think it's great."
Clashes were also reported in the Amazon jungle city of Belem, Porto Alegre in the south, the university town Campinas north of Sao Paulo, the northeastern city of Salvador and dozens of other towns.
The protests took place one week after a violent police crackdown on a small demonstration against an increase in bus and subway fares in Sao Paulo galvanized Brazilians to take their grievances to the streets.
The unrest is hitting the nation as it hosts the Confederations Cup soccer tournament, with tens of thousands of foreign visitors in attendance. It also comes one month before the papal visit, and ahead of the 2014 World Cup and 2016 Olympics, raising concerns about how Brazilian officials will provide security.
Brazilian bishops called a press conference Friday to discuss the papal visit in light of the protests, but no announcement of any changes had been made.
Mass protests have been rare in this country of 190 million people in recent years, and the mushrooming demonstrations of the past week caught Brazilian government officials by surprise while delighting many citizens.
"I think we desperately need this, that we've been needing this for a very, very long time," said Paulo Roberto Rodrigues da Cunha, a 63-year-old clothing store salesman in Rio.
Despite the energy on the street, many protesters said they were unsure how the movement would win real political concessions. People have held up signs asking for everything from education reforms to free bus fares while denouncing the billions of public dollars spent on stadiums in advance of the World Cup and the Olympics.
"This is the start of a structural change in Brazil," said Aline Campos, a 29-year-old publicist in Brasilia. "People now want to make sure their money is well spent, that it's not wasted through corruption."