The Egyptian military removed Mohamed Morsi from power July 3. A member of the Muslim Brotherhood's Freedom and Justice Party, he was the only president elected by a democratic vote in Egyptian history.
Morsi's administration faced mounting criticism for seemingly favoring Islamic principles and for failing to address Egyptian economic woes.
Hundreds of people were killed during clashes last month between Morsi's supporters and Egyptian security forces. Morsi and several high-ranking Brotherhood officials are in custody.
The Brotherhood said in a statement Thursday the "extreme cruelty" employed by the military-led government is a "sure measure" of its weakness.
"The issue has become a clear and unambiguous: the people support the peaceful fight for freedom, dignity and sovereignty, while a group of generals want to enslave the people and rule over them with iron and fire," it said.
Egyptian Interior Minister Mohamed Ibrahim escaped a bomb attack Thursday unharmed. Egypt's al-Ahram Online described the bombing as an assassination attempt. There were no claims of responsibility. The Brotherhood condemned the attack, which left more than dozen people injured.
The Brotherhood said the July 3 ouster was a military coup. Western governments have been reluctant to embrace the categorization officially because it would trigger legal restrictions on foreign aid.