Military jets thundered overhead and troops deployed at strategic sites on Friday as supporters and opponents of deposed Egyptian president Mohamed Morsi, of the Muslim Brotherhood, returned to the country's streets and squares in rival rallies.
In Cairo, the tens of thousands of Morsi loyalists demanding his reinstatement far outnumbered opponents who gathered in the evening in Tahrir Square to celebrate his fall, and at Itthadiya presidential palace in Heliopolis.
Interior minister Mohamed Ibrahim announced that supporters of Mr Morsi's Muslim Brotherhood would not be permitted to reach Tahrir Square, while troops fired tear gas to disperse pro-Morsi supporters who attempted to march to Ittihadiya palace.
Earlier pro-Morsi marchers attempted to augment protests with civil disobedience. They occupied the October 6th bridge spanning the Nile, blocking traffic on a main artery linking the eastern and western sectors of the vast metropolis with 20 million inhabitants.
Scores stormed the gardens of Abbasiya mental hospital and set up camp as others marched toward the defence ministry, chanting “Peaceful, peaceful,” but were halted by troops.
One group of marchers was stoned by residents of the ancient Khan al-Khalil market area near 1,000-year old al-Azhar University, the global seat of Sunni learning.
Tens of thousands gathered at Rabaa al-Adawiya mosque in Nasr City where thousands have camped for three weeks. Some attempted to march to the nearby presidential guards barracks where Mr Morsi was initially held, but were turned back by troops.
The Brotherhood’s huge encampment has prompted neighbourhood residents’ committee to give organisers a deadline to turn off sound systems late at night and prevent demonstrators from blocking side streets and invading gardens and buildings.
In the port city of Alexandria supporters mocked army chief Abdel-Fattah El-Sisi, who removed Mr Morsi from the presidency.
The demonstrations had extra emotional significance since, according to the Muslim calendar, they took place on the 40th anniversary of the 1973 Arab war with Israel, a conflict regarded as a victory by many Arabs since Egypt and Syria, initially, pushed Israel out of territory occupied in 1967.
Ahead of the day of mass action, army spokesman Ahmed Ali warned against deviating from “peaceful means of expression..[and] violence or vandalism.”
Caretaker president Adly Mansour said, “We are going through a critical stage. Some of us want to move towards chaos and we want to move towards stability. Some want a bloody path,” but the government is committed to security and stability. “We will fight the battle for security until the end. We will preserve the revolution.”
The Brotherhood did not budge from its demands. Spokesman Gehad Haddad stated, “Restoring legitimacy is non-negotiable.”
While he slammed the EU's failure to condemn the army "coup" that ousted Mr Morsi after foreign policy chief Catherine Ashton met several move- ment figures, Mr Haddad has proposed that EU envoy Bernardo Leon facilitate talks. However, he ssaid the Brotherhood insists that dialogue can take place only once Mr Morsi and the controversial constitution have been restored.