More than 900 people were injured as clashes erupted between riot police and protesters in Tahrir Square in the Egyptian capital Cairo on Saturday, health officials said on Sunday.
The clashes come nine days before Egypt's first elections since former President Hosni Mubarak was ousted in February.
Qatar-based Al Jazeera broadcaster reported that the violence started when riot police used force to dismantle a small tent camp, established to commemorate earlier killed demonstrators, and attacked some 200 peaceful protesters who had camped out in the square overnight.
At least two people are reported dead in Cairo and Alexandria.
Some 50,000 protesters gathered in Tahrir Square on Friday to take part in rallies against military rule called "Friday of One Demand."
The protest, also dubbed "Friday of Protecting Democracy," was one of the largest in the past few months. Demonstrators called on the military government to transfer power to an elected civilian cabinet.
The reason for the protest was a document on "supra-constitutional principles" recently presented to political parties by Deputy Prime Minister Ali al-Silmi. The document would shield the armed forces from public scrutiny.
Nine months after the ousting of Mubarak, Egypt is still ruled by a military government unwelcomed by much of the population. The date for transfer of power to a civilian cabinet has not yet been set.