With 10 months to go to the Confederations Cup and as the countdown starts to the 2014 World Cup, Brazilian officials said on Monday that they will not tolerate fan violence.
The country, which lasted hosted the World Cup in 1950, is setting up a specialist police investigation centre to deal with cases of hooliganism, secretary for security affairs for Rio state, Jose Mariano Beltrame, told reporters, adding it would be based in the swish suburb of Leblon.
The news came on the heels of several outbreaks of fan violence at club level, with 21 knuckle duster-wielding fans of Fluminense arrested on Sunday for attacking two fans of another local side, Vasco da Gama.
"We can no longer tolarate violence ... this is not an example of (the image) we wish to project at the World Cup. We must act with rigour," Marta Rocha of the civil police authority told O Dia daily.
The mother of one of those arrested told reporters: "I am ashamed of my son."
Police lieutenant-colonel Joao Fiorentini explained that the 21 had been thrown in the cells as "quite apart from the assault, there was theft and that is why they have been locked up. We are tightening the noose."
Leaders of the 'Young Flu' supporters club said those responsible faced being thrown out of the club.
Last week, a Vasco fan, Diego Leal, was killed by thugs supporting Flamengo and last April a Flamengo fan, Bruno Saturnino, was beaten to death by rivals from Vasco.
Also last week, the civil police authority asked the judicial prosecutor general's office to ban Flamengo fans from Rio stadiums.