Casualties have been reported after Egyptian security forces moved on Wednesday to clear two sit-in camps that have sprung up in Cairo in support of ousted President Mohammed Morsi, state television and security officials said.
The Muslim Brotherhood said more than 100 died, but the authorities put the death toll much lower.
State TV showed armoured bulldozers moving deep into the main camp outside the eastern Rabaa al-Adawiya mosque.
Authorities say the Nahda Square camp in western Cairo has been cleared.
The casualty figures could not be independently confirmed.
Reports say police are firing tear gas at the larger of the two protests, in the neighborhood of Nasser City. Television footage shows smoke rising over the protest site, as military vehicles moved toward the camps.
The protesters want Mohammed Morsi, deposed by the military on 3 July, reinstated.
Officials and witnesses said the unrest began Tuesday when hundreds of Morsi supporters marched on several ministries to protest the military-backed interim government installed after the military deposed Morsi on July 3.
Local residents and shopkeepers who backed the ouster threw stones at Morsi supporters marching on the Interior Ministry. The protesters retaliated with stones and police fired tear gas to try to restore order.
Other supporters of the former president remained at two Cairo protest camps, defying days of warnings that the government may soon try to evict them.
More than 250 people have been killed in political violence since Morsi\’s overthrow.
On Tuesday, one person was killed in a confrontation between supporters and opponents of Mr Morsi in Giza after people marched from Nahda Square to a nearby complex of government buildings to protest against the appointment of several military officers as provincial governors.
The interim civilian government is moving ahead with a transition plan that involves reforming Egypt\’s constitution and holding elections early next year.