Hundreds of demonstrators from Islamist parties and groups rallied in Cairo's Rab'aa al-Adaweya Square on Friday morning to participate in a million-man demonstration entitled "Legitimacy is a Red Line".

The demonstrators demand guarding constitutional legitimacy which is one of the most important revolution's gains, the Middle East News Agency (MENA) reported.

They called for standing up to "the attempts of the former regime remnants to ignite strife in the country".

The demonstrators also set up a large platform in front of Rab'aa al-Adaweya Mosque's main gate, the MENA said.

Cairo's traffic department deployed dozens of metal barriers around the area to redirect vehicles away from the square.

The Ministry of Health also deployed a number of ambulances in the area in case of emergencies.

Participants in today's demonstration include the Muslim Brotherhood and its Freedom and Justice Party, the Building and Development Party, the al-Azala Party, the al-Watan Party and al-Gamaa al-Islamiya.