The Egyptian authorities have released 26 women who were detained on Tuesday during the dispersal of a protest against military trials for civilians.
The released detainees were later found on a desert road in the outskirts of Cairo, according to a tweet by activist Salma Said.
At least 24 other protesters are still detained for four days pending investigations, according to an interior ministry statement.
Tuesday counts as the first application of the widely-criticized new protest law on Sunday.
The law mandates that protesters notify the authorities of demonstrations at least three days prior to it. They must also notify the authorities of the number of protesters and slogans they plan to chant.
The police used water cannons and teargas to disperse the protest.
"The arrests that took place during the break up of the protests was because protesters did not follow the required legal procedures to start a protest and not because of the subject of protesting," Interior Minister Aide Abdel Fattah Othman said.