Activists will hold a press conference on Sunday at 6pm to discuss last week's clashes with security forces.
On Tuesday, dozens of activists were arrested in downtown Cairo while demonstrating in defiance of a newly introduced protest law.
The law, issued by the interim government on 24 November, has sparked a chorus of denunciation from rights groups. It forbids demonstrations without prior police consent and violators risk jail sentences and hefty fines.
In the law's first implementation on Tuesday, police fired water cannons and teargas to disperse dozens of protesters who had gathered to condemn an article in the new constitution allowing military trials of civilians.
Dozens of people, including activists, journalists and lawyers were arrested in separate protests on the day.
A number of female activists arrested on Tuesday have filed legal complaints against police officers for assaulting and sexual harassing them, then dumping them on a desert highway.
Twenty four other activists are still being detained pending investigations into accusations of thuggery and attacking public employees, the interior ministry said.
Activists on Sunday accused the interim authorities of seeking to "revive the police state of [former president Hosni] Mubarak, drawing on people's fear of terrorism and unrest."
Numerous unauthorised protests have been dispersed since the law was enacted, and a number of activists have been charged with instigating illegal demonstrations.
Activists have vowed to press on with their street protests to demand the detainees' release, the removal of the interior minister, and an outright ban on military trials of civilians, according to a statement endorsed by groups including The Way of the Revolution Front, No to Military Trials of Civilians and the April 6 Youth Movement.
One protester was killed on Thursday in clashes between supporters of former president Mohamed Morsi and security forces at Cairo University.
Some 200 Brotherhood supporters were arrested on Friday for conducting unauthorised protests and blocking roads.
Interim President Adly Mansour has defended the law, asserting on Saturday that it echoes equivalent French and Swiss legislation.
Prime Minister Hazem El-Beblawi has said the law does not target a particular faction, tacitly referring to supporters of Morsi and his Muslim Brotherhood movement.
The interior ministry said protesting without prior permission violates the law, and warned it would firmly confront such "illegal" acts.
Egypt has been rocked by violent political turmoil since the ouster of Islamist president Mohamed Morsi in July after mass protests against his turbulent one-year reign.
The country's interim authorities have since mounted a sustained crackdown on Islamists, which has seen hundreds killed and thousands arrested.
However, with the new protest restrictions, non-Islamist political groups have voiced fears of a broader clampdown to stifle dissent.