After Muslim Brotherhood leaders gathered supporters in mosques for Friday prayers, their supporters are now marching from north-east Cairo to the city's center in Ramses Square.
According to a BBC News report, all roads leading to Ramses Square in Cairo are being blocked by officials.
A state of emergency is in force and police have been authorized to use live ammunition in self-defense. Officials threw tear gas to disperse crowds marching. Gun shots have been reportedly heard throughout several protesting sites.
BBC journalists in Ramses Square describe the atmosphere as very tense and were advised by the crowd to leave as the area is too dangerous to stay in.
Four new deaths were reported during the clashes in Ismailiya on Suez Canal between security forces and pro-Morsi supporters.
Additionally, reports made by Al-Arabiya say that 15 security force members were killed during an armed attack in the Cairo protests. The violence, which broke out this morning between protesters and security forces in Cairo, has led to at least 638 deaths. Security in the capital is tight, with many armored personnel carriers on the streets.
Morsi supporters started their march from north-east Cairo towards the city's center, chanting "down with military rule".
Meanwhile, barbed wire, armored personnel carriers and armed soldiers were seen blocking an entrance to Tahrir Square, next to the Egyptian Museum, as well as side streets in downtown Cairo.
Defense Ministry Spokesman Ahmed Ali said the military is needed in order to crush violent protests. "When dealing with terrorism, the consideration of civil and human rights are not applicable," Mr. Ali said. "There is insurgency already and it's increasing. They are killing people in the streets."
Citizens of Egypt fear more bloodshed as the protesters fill Egypt's tense streets.