Groups supporting and opposing President Mohamed Morsi held large rallies Friday in Cairo, Ahram Online reported.
Rebel, an anti-Morsi umbrella group, said it had gathered 22 million signatures on petitions calling for Morsi's resignation.
"Morsi has destroyed his own legitimacy even before it was brought down by Egyptians' signatures, after he refused to respect the constitution and preferred the interest of his own group over that of the people," Rebel said in a statement Saturday.
The violence between Morsi supporters and those calling for his resignation led the U.S. State Department to issue a travel warning for Egypt and order non-emergency diplomatic staff to leave the country.
A large protest is planned for Sunday, the first anniversary of Morsi taking office. He was elected in the wake of "Arab Spring" protests that ousted longtime President Hosni Mubarak in 2011.
The government ordered the military deployed to address the latest protests and "avoid the 28 January 2011 scenario," armed forced spokesman Ahmed Ali told state news agency MENA.
Jan. 28, 2011, was marked by anti-government protests involving hundreds of thousands of people in Cairo.
Morsi was elected with the support of the Muslim Brotherhood, whose offices were the targets of protests Friday in several cities in Egypt.
Two people, including Andrew Pochter, 21, of Chevy Chase, Md., were killed at a demonstration near Brotherhood offices in Alexandria. Dozens of people were reported injured, the BBC reported.
Pochter, a student at Kenyon College in Ohio who was in Egypt as an intern for a non-profit group, was apparently killed as he took photographs of the demonstration, the BBC said. There were conflicting reports as to how he was killed.
A protest-related explosion killed another person in Port Said.
The Muslim Brotherhood issued a statement labeling protesters as "thugs."
Protesters have demanded Morsi's resignation since shortly after he took office, claiming he was consolidating power much as the Mubarak regime had.