A court has ordered the release on bail of 84 Morsi supporters detained at Cairo's Al-Fath mosque amid clashes in mid-August.
The court rejected an appeal by prosecutors against a decision to release the prisoners taken days earlier by another court.
The detainees will be released pending investigations into charges including blocking traffic and carrying weapons.
On 14 August, security forces violently dispersed two Islamist sit-ins in Cairo, leaving more than 600 dead and unleashing days of violence.
On 16 August, protesters supporting deposed president Mohamed Morsi and his Muslim Brotherhood group clashed nationwide with security forces and civilians with anti-Brotherhood sentiments.
Some protesters took refuge in Al-Fath mosque, before being arrested the next day by security forces. The violence in central Cairo left more than one hundred dead as both camps were armed.
Since Morsi's ouster, his supporters have faced a widespread security crackdown. Hundreds have died in street clashes with security forces and civilians opposed to the Brotherhood. Thousands of Brotherhood members have also been arrested, including the group's top leadership.