Opponents and supporters of Egyptian President Mohamed Morsi clashed near the presidential palace Wednesday.
Large crowds of supporters of Mr. Morsi converged on the palace as the day wore on, until they eventually outnumbered opponents.
Edward Yeranian in Cairo reports that witnesses say the president's supporters battled opponents and tore down their tents and forced many to flee the area.
Egypt's Muslim Brotherhood had called for a support rally for Mr. Morsi as anti-Morsi demonstrators had remained camped out at Cairo's Tahrir Square and in front of the presidential palace.
The Islamist group said it called the rally because opposition protesters were trying to “impose their opinions through force.”
Meanwhile, U.S. Secretary of State Hillary Clinton called Wednesday for an open dialogue in Egypt.
“The upheaval we are seeing now once again in the streets of Cairo and other cities indicates that dialogue is urgently needed,” Clinton said in Brussels after a two-day NATO foreign ministers meeting.
The opposition protesters want Mr. Morsi to abolish a decree he issued last month granting himself sweeping powers that place him above review by the judiciary.
On Tuesday, Egyptian riot police fired tear gas outside the presidential palace, where tens of thousands of protesters had gathered as Mr. Morsi was inside conducting business. Police tried to stop the crowd from storming the palace but soon retreated and let the marchers through a barrier and up to the palace walls. Egyptian officials say Mr. Morsi had left the palace during the march.
Many of the marchers chanted the same anti-government slogans used in the uprising that toppled former authoritarian president Hosni Mubarak.
Protest leaders called Tuesday's march a last warning to Mr. Morsi to back down from his decree. They are also against a draft constitution that the opposition says was drawn up by Islamists, without input from secularists and liberals.
A referendum on the constitution is set for December 15.