The youth died instantly after being shot in the chest on Sunday, a local district police spokesman told Reuters.
"We are investigating ... The accusations and accounts we have are that (the fighting) was over control of tickets," the spokesman for the Lima district of Ate said.
He was referring to free tickets clubs give their hardcore fans, who are in many cases divided into factions.
The incident occurred before Universitario lost a first division match 3-1 to Sport Huancayo.
"While there are no guarantees to avoid violent acts, we won't give (the club) a licence to operate," Ate district mayor Oscar Benavides said.
Benavides told reporters that Universitario, one of Peru's biggest and most popular clubs, had 30 days to submit a report on security at the stadium.
Television footage showed dozens of riot police with helmets and shields guarding the 70,000-capacity venue to enforce its closure.
Directors of Universitario, South American Libertadores Cup runners-up in 1972, were unavailable for comment.
(Reporting by Marco Aquino; Writing Rex Gowar in Buenos Aires; Editing by Peter Rutherford)
