Supporters of Egypt's deposed president will stage a "Friday of martyrs" of mass protests, risking more potential bloodshed to show they can still claim the streets after a week in which hundreds were gunned down and their leaders jailed.
Egyptians are enduring the bloodiest civil unrest of their modern history after the military overthrew Mohamed Mursi on July 3 following demonstrations against his rule.
In a symbolic victory for the army-dominated old order, former autocrat Hosni Mubarak - toppled in a 2011 pro-democracy uprising - was freed from jail on Thursday, while his freely elected successor Mursi remains imprisoned.
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A seven-week standoff turned into a bloodbath when the security forces dispersed Mursi's supporters' protest camps on Aug. 14. They have since launched a campaign of arrests designed to break Mursi's 85-year-old Muslim Brotherhood, seizing figures that include its "general guide", Mohamed Badie.
At least 900 people, including 100 soldiers and police, have been killed in the past eight days, according to government sources. Brotherhood supporters say the real figure is far higher.
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In recent days, Brotherhood protests that once attracted tens of thousands of people at locations across the country have ebbed, suggesting the group's famed organisational strength may have been damaged by the arrest of its leaders. Friday's protests will be a test of its resilience.
"We will remain steadfast on the road to defeating the military coup," a pro-Mursi alliance called the National Coalition to Support Legitimacy and Reject the Coup said in a statement. It named 28 mosques in Greater Cairo as points of departure for the protests.