Investigators looking into Tuesday's protest and subsequent break-up by police have claimed one protester assaulted a police officer.
The protester also attempted to steal the police officer's radio device, investigators claimed.
An earlier Interior Ministry statement also claimed police dispersal tactics came in response to volleys of rocks from protesters, although photographs and video footage from the scene did not bear this out.
Prosecutor General Hesham Barakat has commissioned Interior Ministry investigators to study Tuesday's events while mandating security forces to apprehend others for prosecution.
On Wednesday prosecutors ordered the arrest of April 6 youth movement leader Ahmed Maher and Alaa Abdel Fattah, both well-known activists from Egypt's 25 January revolution.
Investigators claimed April 6 organized the protest on Qasr al-Aini street in downtown Cairo without consulting authorities or applying for permission to demonstrate, as per Egypt's controversial new protest law.
In total 24 defendants are set to serve four days in prison pending investigations.
Prosecutors have accaused the defendants of forming crowds, organizing a demonstration without notifying the competent authorities, possession of bladed weapons, disrupting the interests of citizens and exposing them to danger, blocking the road, insulting a public officer while performing his job , robbery and thuggery.
Edited translation from Al-Masry Al-Youm
