Three supporters of ousted Egyptian president Mohamed Morsi have been killed and several wounded by gunfire after Egyptian troops opened fire on demonstrators as they marched on a barracks in Cairo where the deposed president was being held.
Islamist allies of Morsi called for a Friday of protests calling it "a day of rejection" to protest against the overthrow by the army of the first Egyptian president elected in democratic elections.
Tens of thousands chanted "Down with military rule" as they marched along a boulevard and pledged to continue their demonstrations until the Muslim Brotherhood's leader was returned to his position as elected president.
The military took over on Wednesday after four days of mass protests by millions of ordinary Egyptians demanding his removal and protesting against what they said was a betrayal of the revolution that ousted dictator Hosni Mubarak.
Morsi has been accused of putting power in the hands of his own Muslim Brotherhood and other Islamists.