Egyptian state media say a 13-year-old boy has been shot dead during clashes in Port Said after the Egyptian city's football team was suspended from playing matches.
Al-Masry, one of Egypt's top teams, has been banned for two years over violence at its stadium in February in which at least 74 people died.
Egyptian officials say dozens of people were also injured as hundreds of angry fans of the Al-Masry club battled security forces on March 24.
Troops fired into the air to try to disperse the crowds after protesters overran a government building.
Reuters news agency says tensions remain high as the harbor was closed and roads into the city were blocked.
Based on reporting by the BBC and Reuters