Spokesman for the Freedom and Justice Party in Cairo, Ahmed Sobei, was arrested on Friday afternoon at his residence in Helwan, south of the capital.
The Freedom and Justice Party is the political wing of the Muslim Brotherhood, from which ousted president Mohamed Morsi hails. Morsi supporters held protests on Friday in various districts around Cairo and in other cities in Egypt.
Al-Ahram Arabic news website reported that Osama El-Sagheer, head of Cairo’s security directorate, has ordered that Sobei be referred to the prosecution on charges of "inciting violence."
Hundreds of Muslim Brotherhood members and leaders have been arrested since the bloody dispersal of two pro-Morsi protest camps in Cairo in mid-August.
Those behind bars include Brotherhood spiritual leader Mohamed Badie and his second-in-command Khairat El-Shater, in addition to deposed president Mohamed Morsi, who has been held incommunicado since his ouster in July. All three Islamist leaders face charges related to the incitement of violence.
On Wednesday, EU foreign policy chief Catherine Ashton met with Muslim Brotherhood leaders Amr Darrag and Mohamed Ali Bishr in Cairo as part of a three-day visit which is being viewed by analysts as an a new attempt to reach an agreement between the post-Morsi government and the Muslim Brotherhood.
According to Al-Ahram, the agreement would be that the Brotherhood will put an end to their anti-military protests in exchange for the release of those arrested without charge.
The pro-Morsi National Alliance to Support Legitimacy has called for continuous rallies starting Friday until Sunday, a national holiday celebrating the 1973 war against Israel, to demand an end to what they describe as a military coup against Morsi.