Prosecutors in Nasr City began interrogating 21 pro-Muslim Brotherhood student protesters from Al-Azhar University over clashes that erupted between demonstrating students and security forces.
The students are charged with assembling, sabotage, protesting without a permit, possessing incendiary substances while protesting, threatening public security, using force against the police, disrupting traffic, destroying three police vehicles and setting trees on fire.
The investigation's report said the remains of Molotov cocktails and pelted rocks were at the scene of the incident.
On Monday, clashes with security forces caused a private bus to be torched by demonstrators.
Students at the university have stepped up protests since a fellow student was killed on campus in clashes by security forces 21 November. The victim was a sixth year medical student named Abdel Ghany Mohamed Hamouda. Students have vowed to continue protesting until the perpetrator of Hamouda's death is brought to justice.
Edited translation from Al-Masry Al-Youm