Seven people were shot dead in the Egyptian city of Suez during nationwide protests against President Mohamed Mursi today, underlining the country's deep divisions on the second anniversary of the uprising that toppled Hosni Mubarak.

One of the dead was a policeman, medics said. Another 456 people were injured across Egypt, officials said, in unrest fuelled by anger at Mursi and his Islamist allies over what the protesters see as their betrayal of the revolution.

Mursi said the state would not hesitate in "pursuing the criminals and delivering them to justice". In a statement, he also called on Egyptians to respect the principles of the revolution by expressing their views peacefully.

The Jan. 25 anniversary laid bare the divide between the Islamists and their secular rivals.

The schism is hindering the efforts of Mursi, elected in June, to revive an economy in crisis and reverse a plunge in Egypt's currency by enticing back investors and tourists.

Inspired by the popular uprising in Tunisia, Egypt's revolution spurred further revolts across the Arab world. But the sense of common purpose that united Egyptians two years ago has given way to internal strife that already triggered bloody street battles last month.

Thousands of opponents of Mursi massed in Cairo's Tahrir Square - the cradle of the revolt against Mubarak - to rekindle the demands of a revolution they say has been hijacked by the Muslim Brotherhood, the group from which Mursi emerged.

In Suez, the military deployed armoured vehicles to guard state buildings, witnesses and security sources said, as symbols of government were targeted across the country.

Street battles erupted in cities including Cairo, Alexandria, Suez and Port Said. Arsonists attacked at least two state-owned buildings. An office used by the Muslim Brotherhood's political party was also torched.

"Our revolution is continuing. We reject the domination of any party over this state. We say no to the Brotherhood state," Hamdeen Sabahy, a popular leftist leader, told Reuters.

The Brotherhood decided against mobilising for the anniversary, wary of the scope for more conflict after December's violence, stoked by Mursi's decision to fast-track an Islamist-tinged constitution rejected by his opponents.

The Brotherhood denies accusations that it is seeking to dominate Egypt, labelling them a smear campaign by its rivals.