On 1 February 2012, a riot broke out at Port Said Stadium in Port Said, Egypt, after an Egyptian Premier League match in which home club Al Masry defeated Al Ahly 3–1. After the final whistle, thousands of Al Masry supporters invaded the pitch and attacked Al Ahly fans and players with clubs, stones, machetes, knives, bottles, and fireworks, trapping Al Ahly supporters inside their section of the stadium. Witnesses said police did little to stop the attackers and refused to open locked stadium gates, and many of the deaths resulted from a stampede as fans tried to escape through the closed gates. Seventy-four people were killed and more than 500 were injured; the Egyptian deputy health minister called it the biggest disaster in the country's football history, in comments quoted by the BBC. An Egyptian health ministry official said stab wounds, brain hemorrhages, and concussions caused the deaths. The Egyptian army airlifted soldiers by helicopter to rescue Al Ahly players, who were trapped in their locker room. Al Ahly head coach Manuel José was kicked and punched by Al-Masry supporters while trying to return to the locker room and was later taken to a police station.
The disaster set off civil unrest and clashes with police in Cairo, Alexandria, and Suez. The Egyptian Football Association postponed the season's remaining matches and, on 10 March 2012, cancelled the rest of the 2011–12 season; the Egyptian government subsequently suspended the domestic league for two years. News commentary, including from the New York Times and an ESPN columnist, noted that many of the Al Ahly fans present belonged to Ultras Ahlawy, a group that had taken part in the 2011 Tahrir Square protests against the ruling Supreme Council of the Armed Forces, and raised the possibility that the riot was retaliatory or politically motivated; these accounts describe this as an allegation rather than an established finding. In 2015, footballer Mohamed Salah, on loan at Italian club Fiorentina, wore squad number 74 in tribute to those killed.
Seventy-three defendants — including nine police officers and two Al-Masry club officials — were charged over the killing of 72 Al Ahly supporters. On 26 January 2013, a Port Said court issued preliminary death sentences to 21 defendants; it confirmed those sentences on 9 March 2013 and issued sentences ranging from one to fifteen years, and life terms, to most of the remaining defendants, while acquitting 28, including seven police officers and both charged Al-Masry club officials. Unrest linked to the verdict near Port Said General Prison left two police officers and 40 civilians dead. Egypt's Court of Cassation ordered a retrial of 64 defendants in February 2014. In the retrial, the court issued 11 preliminary death sentences in April 2015, confirmed them in June 2015 while acquitting 21 defendants, and in August and November 2015 resolved sentences for defendants tried in absentia. Egypt's Court of Cassation upheld the final death sentences on 20 February 2017; contemporary reports counted 10 of the 11 as upheld. In total, of the original 73 defendants, 47 were convicted and 26 were acquitted as of 15 November 2015.