Sao Paulo, Mar 26: A fan was shot to death and three were hospitalized in a serious condition after a fight between rival supporter groups in Brazil on Sunday.
Andre Alves, 21, was killed with a shot to the head in a confrontation that involved nearly 500 fans before a match between rival clubs Corinthians and Palmeiras.
One of the three fans in serious condition was shot in the hip and had to undergo surgery. The nature of injuries to the other two men were not immediately made available. Three people were treated and released.
Witnesses told local media that Alves was among a group of Palmeiras fans who got ambushed by several Corinthians supporters in the city's north side.
The fans fought with iron bars, pieces of wood and rocks. Police had to use tear gas and rubber bullets to halt the confrontation Sunday morning.
Four people were detained, but it wasn't clear if they were suspected of shooting Alves.
Police were investigating reports that the fight was set up ahead of time on social media networks.
Last year, a Corinthians fan was killed by Palmeiras supporters before the teams' match in the Brazilian league. Nobody was arrested then.
Corinthians won Sunday's match 2-1 and there were also some minor incidents inside the Pacaembu stadium, although no injuries were reported.
Fan fighting is common in Brazil before matches between traditional rivals. It happens mostly in Sao Paulo and Rio de Janeiro, although there are problems in other regions of the country from time to time.
Earlier this week, authorities prohibited fan groups from Campinas city rivals Guarani and Ponte Preta from attending their teams' matches because of fighting that led to the death of a fan. The ban started on Saturday, when Guarani drew Ponte Preta 1-1.
In November 2010, a 19-year-old Cruzeiro fan was killed after being repeatedly beaten with iron bars during a brawl between dozens of rival fans in Belo Horizonte in southeastern Brazil.