REPORTING FROM CAIRO -- More than 500 protesters were injured Saturday in clashes with riot police in another eruption of Egyptian anger before next week's parliamentary elections.
The violence broke out when security forces moved to evacuate about 200 protesters who had staged a sit-in late Friday after a massive rally against plans by the nation's ruling generals to increase the military's power in a new constitution.
Hundreds more demonstrators marched on the square early Saturday as police fired tear gas and rubber bullets to stop protesters from reaching the nearby Interior Ministry.
By nightfall, as a police vehicle was set ablaze, several thousand people remained in the square after security units pulled back. It was unclear whether demonstrators were planning to stay overnight; none of the country's major political groups or activist movements had planned to occupy Tahrir beyond Friday evening.
"The people want the downfall of the field marshal," chanted some of the protesters, referring to the head of the ruling Supreme Council of the Armed Forces, Mohamed Hussein Tantawi. Others directed their slogans against the Interior Ministry, calling riot police forces "thugs and thieves."
The clashes came as the military-backed government appeared to make concessions on the drafting of the constitution -- a main objective of protesters.
Deputy Prime Minister Ali Selmi announced amendments for the constitutional guidelines that would limit the military's role to preserving the country's unity. The provision originally stated that the military would be the guardian of "constitutional legitimacy," a phrase many interpreted to mean the generals would hold sway over parliament and the president.
The amendments also stated that the military would "abide by the constitutional and legislative regulations" like any other government agency.
Saturday's clashes were among the most violent since the Supreme Council took control of the country after the fall of Hosni Mubarak in February. Prime Minister Essam Sharaf issued a plea asking everyone in Tahrir to evacuate the square, the state news agency MENA reported.
The police response prompted condemnation from political forces and human rights advocates.
The Egyptian Organization for Human Rights issued a statement dubbing violent events as "a grave development in the course of events in Egypt, as it gives the impression that nothing has changed since the Jan. 25 revolution in terms of the police's treatment of peaceful protesters."
The Egyptian Journalists' Union has also criticized police actions against a number of reporters covering Saturday's events. The police said 40 of its officers were injured. An unnamed Interior Ministry official was quoted by state TV as saying that security forces practiced self-control when dealing with protesters.
The clashes came nine days before the start of parliamentary elections, which will be carried out over three phases starting Nov. 28 and ending Jan. 10.
The violence underscored the growing frustration against the military, which has repeately delayed handing power to a civilian government.
Photo: Egyptian protesters surround a police vehicle during clashes with security forces in Cairo. Credit: EPA