Hundreds of people suffered injuries during the clashes, which drew in bystanders and saw all sides hurling stones and Molotov cocktails at each other.
Student supporters of the Ahly Club took to the roof of the dorms and pelted passers-by with stones and Molotovs while raising red T-shirts with the number 22 written on them, in a reference to Ahly Club player Mohamed Abu Treika.
Dozens of people were transferred to Port Fouad Public Hospital, and police fired tear gas canisters at bystanders and inside dormitories. One canister was thrown inside the Canal Company's building for navigational constructions on the Suez Canal's eastern side, affecting hundreds of employees.
Central security forces and police troops eventually moved back to areas around the dormitories after withdrawal.
Unconfirmed news reports said that local university students detained four people, including two Al-Masry Club ultras and two Port Said security personnel
Edited translation from Al-Masry Al-Youm