Clashes in Egypt have continued early Tuesday, despite a plea from the country's interim president urging people to remain calm and abstain from violence.
Supporters of ousted President Mohamed Morsi were involved in fighting Tuesday near Cairo University's main campus in Giza, where police broke up the violence.
Hours earlier, Interim President Adly Mansour spoke on state television, telling Egyptians that reconciliation is necessary for the country to move forward.
Clashes Monday between supporters and opponents of Mr. Morsi left four people dead and dozens more wounded.
Security officials said Monday's fighting started with stone-throwing when a group of Morsi supporters passed near Tahrir Square during a protest march.
Mr. Morsi's family has spoken out against Egypt's military, accusing it of kidnapping him. The former president's son, Osama Morsi, threatened to use legal measures to gain his father's release.
At a news conference Monday in Cairo, Osama Morsi said the family has not seen their father since July 3 when Egypt's military overthrew Mr. Morsi's democratically elected government.
Military officials say they have detained Mr. Morsi for his own protection and that he is in good health.
Mr. Morsi's Muslim Brotherhood has been holding near daily demonstrations in Cairo and across the country, demanding his release and reinstatement. He had served only one year of his term as Egypt's first democratically elected president following the removal of longtime leader Hosni Mubarak in 2011.