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 prostest, 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."
Mothers carrying babies marched and chanted, "Revolution until Victory!" while young men parked their cars on the main street and waved signs.
The noisy crowd was joined by cars driving alongside and honking their horns. People cried "Long Live a Free Tunisia," and waving Tunisian and Egyptian flags while police initially stood on the crowd's periphery.
The rallies came against a backdrop of growing anger in Egypt over widespread poverty and unemployment, as well as questions about whether Mr Mubarak will run again in presidential elections later this year or perhaps position his son to run.
The first ramifications of the Tunisia uprising surfaced last week in Egypt when several people set themselves on fire outside parliament and the prime minister's office.
Their actions sought to copy a young Tunisian vegetable seller whose self-immolation helped spark the protests that forced Tunisia's authoritarian president to flee the country.
Nearly half of Egypt's 80 million people live under or just above the poverty line set by the United Nations at 2 dollars a day. Poor quality education, health care and high unemployment have left large numbers deprived of basic needs.
Soon after the removal on January 14 of Tunisia's president Zine El Abidine Ben Ali, all eyes focused on Egypt, with observers wondering if the dramatic events in the North African nation could spur unrest against another entrenched Arab regime.