A coalition of largely Islamist parties and groups supportive of ousted President Mohamed Morsi has called for mass rallies on Friday to protest the military coup against Egypt's elected head of state.
Morsi, Egypt's first democratically elected president, was ousted by the powerful army on July 3 after mass demonstrations against his regime.
Ever since his removal, thousands of demonstrators have been staging daily protests and sit-ins to defend Morsi's "democratic legitimacy" and demand his reinstatement.
The two largest sit-ins have been staged in Rabaa al-Adawiya Square in eastern Cairo and Nahda Square in Giza.
The Egyptian government on Wednesday said that the continuation of the two pro-Morsi sit-ins constituted a "threat" to Egypt's national security.