At least 22 people were killed on Sunday evening when fans of the Egyptian Zamalek soccer group clashed with Egyptian police before a Premier League game, the Al-Ahram website reported.
Egypt's prosecution said the bodies of the victims were transferred to a Cairo morgue. State news agency MENA said at least 25 were injured.
"They died of suffocation and stampede after being tear-gassed," a medical source at the Ahli Bank Hospital, which received 14 bodies, told Al-Ahram.
Police used tear gas to disperse members of the group of hardcore fans of the team, known as the Ultras White Knights, in front of Cairo's Air Defense Stadium, an army-owned venue, a few hours before Zamalek played.
Ultras White Knights shared photos of alleged bodies of the victims on its official Facebook page, some of which wearing the team's jersey, as well as a full list of their names.
The Egyptian interior ministry said the clashes occurred after Ultras White Knights members tried to attend the game without buying tickets.
"The Zamalek fans tried to get in by force, and we had to prevent them from damaging public property," the ministry said in a statement quoted by Al-Ahram.
The incident is reminiscent of one which took place three years ago, in February of 2012, when more than 70 people were killed and hundreds injured in post-match violence following a game in Port Said between Cairo's Al-Ahly and Al-Masry.
The riots, considered at the time the deadliest in Egypt's sports history, were largely blamed on supporters of Hosni Mubarak, who was ousted in early 2011 after a popular uprising.