Brazil's biggest protests in decades are a confusing, conflicting mix of people and messages. Blame Facebook.
Social media tools like Facebook and Twitter enabled mass protests of the sort that have not happened in Latin America's biggest country in more than two decades.
As a result of the speed, efficiency and anonymity of online activism, though, an amorphous, unwieldy movement has emerged that is beyond the control of any of those who first began pushing for change.
"Social media has helped us organize without having leaders," said Victor Damaso, 22, demonstrating on Sao Paulo's main Paulista Avenue on Thursday night. "Our ideas, our demands are discussed on Facebook. There are no meetings, no rules."
The demonstrations have been mostly peaceful, but as more than a million Brazilians took to the streets on Thursday, vandals and looters cast a violent pall over some of the protests. Police and security forces have responded with teargas, rubber bullets and pepper spray.
Facebook pages set up for logistical coordination and Twitter hash tags have cropped up for protests in hundreds of cities across Brazil. Rival groups appear to be vying for control of one of the most-viewed organizing pages on Facebook and an associated Twitter feed.
"Any movement risks attracting unaffiliated groups and individuals," said Angela Alonso, a sociologist at the University of Sao Paulo. "It's a price of growth. In this case there is no centralized leadership, administration is more difficult and it is even becoming uncontrollable."
The Free Fare movement, a group of 40 activists who marched for - and got - lower transportation rates, said on Friday it was suspending any further marches for now because of mounting tension and violence.
Sparked by Free Fare's protests, the nationwide call for reform quickly evolved into what is now known online as Anonymous Brazil.
The group appears to use encrypted Web browsers that make it difficult to identify page administrators and has adopted the Guy Fawkes mask, the symbol for the global cyber group of hackers known as Anonymous, as its mascot, although it is not clear if the two have a formal link.
While that opens the door to all sorts of fringe groups, the people at the core of the protests generally share a commitment to better public services. Their rallying cries, found on Twitter and Facebook and on traditional signs at the protests, range from ending political corruption to lambasting more than $12 billion being poured into soccer stadiums and other preparations for the 2014 World Cup.
The demonstrators, mostly educated, middle class and under age 30, want nothing to do with established groups that were behind the causes of their parents' generation.
Unlike Brazil's movement for redemocratization in the 1970s and 1980s and protests for the impeachment of President Fernando Collor de Mello in the early 1990s, today's demonstrations have no clear leadership or political affinity.
"The recent protests are not partisan, and they do not have centralized leadership," said Alonso, the sociologist. "This has to do with new technologies that allow for organization without centralization, and also with the fact that the activists are from a new generation that is no longer guided by ideals like socialism, and doesn't want state power."
Indeed, Brazil's protests do not target any specific leader or political party. That makes them different from the Arab Spring, a series of uprisings against autocratic leaders in the past few years, or even this year's demonstrations in Turkey against the government of Prime Minister Tayyip Erdogan.
While some of the Arab governments blocked access to the Internet to disrupt the planning of protests, Brazil's intelligence agency, Abin, has beefed up efforts to monitor calls for demonstrations online and on popular smart phone chat tool WhatsApp.
President Dilma Rousseff, a leftist guerrilla in the 1970s, has praised the protests as democratic.
Anonymous Brazil's Facebook page, which has nearly 1 million followers, briefly disappeared from the Web on Friday. The group later said via Facebook that its Twitter account had been "robbed" by one of its own members, generating conflicts on its linked Facebook platform.
The group says competing Twitter accounts like @AnonymousBr4sil and #AnonymousFuel are run by "usurpers."
Of the 53.5 million Brazilians online, almost a third of the population, 86 percent use some kind of micro blog or social media tool, according to polling firm Ibope.