Brazil's organisational reputation, already under fire in the run-up to the World Cup, suffered another blow Sunday when three spectators were seriously hurt in violent clashes at a league match.
Police said that fans of Atletico Paranaense and Vasco da Gama fought running battles in the stands at the Santa Catarina stadium from as early as the 17th minute when Atletico took a 1-0 lead.
A police helicopter was forced to land on the pitch to bring the violence to an end and medical help to the injured.
The match was held up for an hour before being restarted.
"It's regrettable to see these type of things at this time when everyone is talking about the next World Cup in the country," said Vasco technical director Adilson Batista.
Police blasted the arrangements at the ground where private security had been employed.
"The forces of law and order intervened later because security at the match was under the responsibility of a private company employed by Atletico," said police spokesman Adilson Moreira.
"The military police were patrolling the outside of the ground."
Paranaense technical chief, Vagner Mancini, said he was shocked by the fighting.
"I have never seen such scenes. It made us want to leave the stadium and go home," he said.
Santa Catarina, in the south of the country, is not hosting a match in the World Cup which starts on June 12.