The Egyptian presidency ordered forming a judicial committee to investigate killings that took place outside the Republican Guard headquarters early Monday morning, official news agency MENA reported.

The bloody clashes left at least 42 people killed, most of them alleged by the Muslim Brotherhood (MB) as supporters of ousted President Mohamed Morsi, accusing the security forces of firing on the protesters during their dawn prayers.

Meanwhile, MENA reported that two policemen were killed and six others injured in the same clashes, while the army revealed one officer was killed and 40 soldiers were wounded.

Voicing regrets about the victims of the "agonizing" incident, the presidency called for "self-discipline," and stressed on the necessity of prioritizing the national interests and the national security of the state.

Meantime, the presidency emphasized that peaceful protest is a right guaranteed for all people and called all protesters not to attack the vital premises and the military facilities, appealing to all sides in the state to achieve a national reconciliation in order to achieve the transitional period as soon as possible.

On Wednesday, the army ousted Morsi after millions of people took to the streets to protest the Islamist president's "poor performance" since he took office a year ago.