The day started with clashes in the morning between liberals who oppose Mursi's decisions and have been camped out in the iconic Tahrir square since Friday and his supporters who tried to burn the sit-in tents down.
Egypt's military erected a new wall near Tahrir Square as clashes continued between police and protesters angry at President Mursi's Constitutional Declaration.
The crisis also struck the country's stock exchange with share prices plunging almost 9.5 per cent.
A statement issued by the Muslim Brotherhood asked its supporters to hold agitations this afternoon in all of Egypt's main cities to "support the decisions of the President."
It also announced a "Million Man" demonstration Tuesday at Abdeen Square in Cairo to support Mursi.
Since Mursi made his announcement Thursday, assuming far-reaching powers, at least 261 people have been injured in clashes in Cairo and elsewhere, media reports said.
The Brotherhood backed the President's decree saying it was a necessary move to prevent the courts disbanding the Islamist-dominated panel drawing up a new constitution.
The judges slammed the President's move yesterday denouncing it as "an unprecedented attack on the independence of the judiciary and its rulings" and calling for the courts to stop work nationwide.
Judges in two of the country's 27 provinces, including Mediterranean metropolis Alexandria, heeded the strike call today.
Tahrir Square, one of the capital's main road junctions, remained closed to traffic today as Mursi opponents pressed their sit-in.
Police fired tear gas as protesters who hurled stones on the third day of demonstrations opposing Mursi's power-extending decree.
