IT WAS THE FINAL ROUND of 2013’s Brazilian Championship. At stake were second place for Paraná’s Atlético Paranaense, and relegation for Rio’s Vasco da Gama. In the stands of Arena Joinville, the host’s landslide win was overshadowed by displays of genuine brutality.

The wildness of the organizadas — as organized groups of hooligans are known in Brazil — resulted in the suspension of the game. Four fans were taken to the hospital, one of them in severe condition. Six men were arrested. Fortunately, no one died.

Next morning, Brazilian sports newspaper LANCE! reported that 234 people had lost their lives in clashes connected to soccer in the past 25 years. The initial death was registered in April of 1988. That victim was the head of Mancha Verde, Palmeiras’ organizada based in São Paulo.

Since the episode in Joinville, one more person has died, a fan of Recife’s Sport FC who was beaten in the head by a toilet in the second tier of Campeonato Brasileiro.

The numbers may seen small in comparison with other countries. The tragedy at Heysel in 1985 alone killed 39 people on account of the irresponsibility of Liverpool’s hooligans. But violence is a serious problem in Brazilian soccer and has its own particularities.

1. Problems typically unfold outside the stadiums.

There were two things out of the ordinary in the clashes between the organizadas of Atlético Paranaense and Vasco. The first is that people were imprisoned. The second is that the violence happened inside the stadiums. That’s rare. Clashes between fans are regularly scheduled on the internet and consummated in the streets.

Twenty-year-old Atlético Mineiro fan Lucas Batista Marcelino was shot and killed by two Cruzeiro fans, on a motorbike, in the east zone of Belo Horizonte, Minas Gerais. It happened in 2009, about 10km from where the clubs were playing.

Three years later, about a thousand fans from Palmeiras e Corinthians turned São Paulo’s north zone into their own Colosseum. The conflict took place at Inajar de Souza Avenue, 10km away from Pacaembu Stadium. Two men were shot.

2. Different sets of hooligans can team up.

There’s no cooperation between fans of local rivals, such as Corinthians and Palmeiras. But organizadas from different states make alliances that are pretty valuable in away games.

Palmeiras’ Mancha Verde, for instance, is friends with Vasco’s Força Jovem. São Paulo’s Independente has an alliance with Flamengo’s Jovem. There are also cases of discrepancies between two organizadas that have led to broken relations. Corinthians’ Gaviões da Fiel and Atlético Mineiro’s Galoucura used to be friends, but now can’t stand each other.

It sometimes ensures peace, but can also make some circumstances worse. Palmeiras’ organizada is even more of an enemy in the eyes of Flamengos because of their friendship with Vascos. The result of this can be seen in the Brazilian episode of “Football Factories,” a series of films about hooliganism. A bus bringing Palmeiras fans back to São Paulo is shot at on the road.

3. Players aren’t immune.

Palmeiras’ former midfielder João Vítor was shopping at the club’s store, on Turiassu street, near the team’s stadium, when he became involved in a fight with Mancha Verde members.

Vagner Love, one of Palmeira’s best strikers in the last ten years, was getting money out of an ATM, also in the vicinity of the club’s stadium, when he was beaten by organizados.

In Brazilian football, players are no safer than the fans in the stands. When the hooligans decide a footballer is not playing well, they forget about swearing and things get real.

This year, a group of criminals invaded Corinthian’s training field, and there were reports of aggression against employees. Mário Gobbi, the club’s president and a police delegate, said striker Guerrero was held by the neck by one of the hooligans.

4. It’s a super homophobic scene.

The squads of European hooligans have an inclination towards ultranationalism and neo-fascist ideologies, and discrimination typically runs rampant against black people and immigrants. There’s prejudice in Brazil as well, and the most common is homophobia.

There was a derby between Corinthians and São Paulo this year, where thousands of corintianos called goalkeeper Rogério Ceni a “fag.” São Paulo is often mocked as “a homosexual team” — as if this were some kind of offense.

Last year, Emerson, Corinthians’ Libertadores hero, with two goals in the final match against Boca Juniors, published a picture on Instagram where he was kissing a male friend. What in the beginning was an exceptional action against homophobia turned out to be a lamentable episode. After pressure from various members of Gaviões da Fiel, he retracted, said he hadn’t meant to offend, and publicly stated that he really prefers women.

Corinthians fans are not the only homophobes in Brazilian football, of course. Atlético Mineiros believe that a good way to offend Cruzeiros is by calling them “Mary.” São Paulo fans stopped singing player Rycharlison’s name because he was seen as gay. The player finally came out as homosexual in 2013.

5. They really like Carnaval.

São Paulo organizadas are also into carnival parades. The headquarters are usually located in the same place where drummers and sambistas rehearse for Carnaval every year. And they are very relevant. The Corinthians-related Gaviões da Fiel, for instance, won the city “special group” four times.

Palmeiras’ Mancha Verde never won a title, but is always on the first tier. As for São Paulo’s Dragões da Real, they have held a place in the Carnival parade “special group” for the past three years.

In 2012, a member of Império da Casa Verde broke into the jury’s space and tore apart some of the votes. Soon after, Gaviões da Field did the same. Corintianos continued the violence by kicking and moving the grids that separated the Sambódromo do Anhembi from the streets.

In 2012 and 2013, the three groups were in the same run — a cause of deep concern for police and authorities.