Egypt’s political stability is once again threatened by renewed rioting across the country’s major cities.

At least 50 people have been killed so far and thousands wounded.

Head of the Egyptian armed forces, General Abdul Fattah al-Sisi, has warned that the continued protesting could result in the collapse of the state and ”threaten future generations”.

Riots first broke out in Cairo on 25 January on the two-year anniversary of the overthrowing of the former president Hosni Mubarak. Protesters have been voicing their dissatisfaction at current Islamist president Mohammed Mursi.

Demonstrations also broke out in Port Said, Suez and Ismalia in protest against the death sentences handed to 21 people for their role in last year’s riots at the Port Said football stadium, which killed 74 people. Supporters of the defendants attacked police stations and two police officers were shot dead near the city’s prison.

President Mursi declared a state of emergency in all three cities close to the Suez Canal and the army was brought in to restore stability. A 30-day curfew has been imposed on the cities.

However, the escalating violence has forced Mursi to cut short his trip to Germany to meet the German chancellor Angela Merkel.

Although the riots in Cairo and Port Said were sparked by different reasons, the protesters are united by a broad sense of frustration at the Mursi government.

The president continues to be criticised for running an autocratic regime, pushing through a constitution that fails to protect freedom of expression and worsening the Egyptian economy. Egypt’s currency has slumped against the dollar in recent weeks and the much-needed $4.8bn support package from the Washington-based IMF continues to suffer delays.

There is also resentment among some about the growing strength of Islamic groups with the Egyptian government. Mursi has his political roots in the Muslim Brotherhood, an organisation banned under the Mubarak regime.