Thousands of anti-government protesters inspired by the Tunisian revolution clashed with riot police in the centre of Cairo today demanding the overthrow of president Hosni Mubarak.

Police responded with water cannon and attacked crowds with batons and  tear gas to clear crowds demanding an end to the country’s grinding poverty.

The protest, the largest Egypt has seen for years, began peacefully, with police showing unusual restraint in what appeared to be a concerted government effort not to provoke a Tunisia-like mass revolt.

As the crowds in central Cairo’s main Tahrir square continued to build, however, security personnel changed tactics and the protest turned violent.

Demonstrators attacked the police water canon truck, opening the driver’s door and ordering the man out of the vehicle.

Some hurled rocks and dragged metal barricades. Officers beat back protesters with batons as they tried to break cordons to join the main group of demonstrators downtown.

To the north, in the Mediterranean port city of Alexandria, thousands of protesters also marched in what was dubbed a ‘Day of Rage’ against Mr Mubarak and lack of political freedoms under his rule.

In another parallel with the Tunisia protests, the calls for rallies went out on Facebook and Twitter, with 90,000 saying they would attend.

The protests coincided with a national holiday honouring Egypt’s much-feared police.

Demonstrators in Cairo sang the national anthem and carried banners denouncing Mr Mubarak and the widespread fraud that plagues the country’s elections. The organisers said the protests were a ‘day of revolution against torture, poverty, corruption and unemployment.’