Marcelo Struminger, president of the doctor's association at Santojanni Hospital, said gang members associated with the Argentina club Nueva Chicago raced through the delivery room and other parts of the hospital on Wednesday looking for the whereabouts of a rival hooligan known as "Aldo The Paraguayan."
He is believed to have been involved in the death Wednesday of Agustin Rodriguez, who was killed in a fight between his faction — known as "Los Perales," — and the rival faction "Las Antenas."
"They ran through the delivery room and pulled out knives and firearms against security personal," Struminger said.
The surreal scene was captured on closed-circuit television and widely shown Thursday on national television.
The camera caught the gang members barging past limited security at the hospital, and then throwing chairs in a hospital corridor as they seemed to be searching for the rival hooligan member.
"They demanded to see one person, the presumed perpetrator who was being treated for stab wounds to the abdomen," Struminger said. "The doctors were afraid, just like everyone else."
No arrests were reported in the case, which took place in a western neighbourhood of Buenos Aires called "Mataderos," which translates in English as "Slaughterhouses."
The neighbourhood has been the traditional home of the city's meatpacking industry, and to the second-division club Nueva Chicago.
Football-related violence has plagued Argentina for years, with non-profit group "Let's Save Football" estimating that almost 260 people have died in such incidents since 1924.
Mayhem threatens many aspects of football in Argentina, with police, hooligan gangs, unions and top-ranking politicians connected in a web of violence.
Matches are regularly called off every season because of fan violence — in and outside the stadium.
Riots broke out seven months ago after famed Buenos Aires club River Plate was demoted to the second division. The loss prompted rampaging fans to set fires inside the club's stadium, with firefighters using high-powered hoses to gain control.
Outside, police on horseback fought running battles with fans, who climbed razor-wire barriers, pelted police with rocks, and set fire to overturned vehicles.
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