The fight erupted Monday when fans of Dock Sud, a club from a working-class neighborhood in the capital, encountered fans of San Telmo, another local club that is the favorite to win promotion to the third-tier league this season.
Neighbors said the clash soon escalated into a gunfight that drew in riot police and claimed at least three victims.
Family members said San Telmo fans Javier Araujo, 29, and Daniel Sanchez, 28, had died of their wounds.
A third victim is in hospital after being hit in the face by a rubber bullet, San Telmo club officials said.
The brawl erupted after separate matches in which Dock Sud drew 0-0 with Talleres de Remedios de Escalada and San Telmo tied 1-1 against Defensores de Cambaceres.
Under a 2013 law aimed at curbing violence by Argentina’s infamous “barrabravas,” or football hooligans, visiting fans are barred from watching matches at the stadium.
The San Telmo fans, whose side was playing away, had set up a giant outdoor screen to watch their team’s match.
San Telmo supporters said the Dock Sud fans ambushed them, a claim they latter denied.
Argentine cabinet chief Jorge Capitanich condemned the brawl.
“These violent acts are crimes committed by murderers who deserve the harshest punishment,” he told a press conference.
The fight came five days after another between rival factions of supporters of third-tier club Almirante Brown left one person dead and a child wounded.
The latest deaths bring the number of people killed in football-related violence in Argentina to 10 so far this year, according to watchdog group Let’s Save Football (SAF).
The group says football violence has killed 195 people in the South American country in the last four decades- AFP