Gunmen set fire to a police station in the east Cairo suburb of Marg on Friday and released the suspects who were being held there, security officials told state TV Friday.
Unrest is simmering nationwide in the wake of the country's worst-ever football disaster in Port Said, which killed 74 people on Wednesday. Over the past three days twelve people have died in protests against the security forces, who are widely seen as responsible for the disaster.
In the neighborhood of Dokki in Cairo, five men stormed another police station and tried to take a policeman's weapon, but he fought them off, according to the same officials.
Cairo, with 20 million inhabitants the largest city in Africa in terms of population density, witnessed high rates of armed robberies, car thefts and attacks on banks last week.
Egypt has faced a surge in crime since the 25 January revolution, which uprooted a police state.
Protesters accuse the police and the ruling military council of deliberate negligence in the face of a security vacuum over the past year.