Thousands of defiant supporters of deposed Egyptian president Mohammed Morsi on Sunday staged a sit-in at Cairo, a day after the Muslim Brotherhood claimed that security forces killed nearly 200 Islamists, opening a deadly new phase of conflict in the deeply polarised country.
Vowing to stand their ground despite violent crackdown on their supporters by armed forces, Brotherhood leaders addressed protesters overnight, saying they would not back down from their demands including reinstatement of Morsi.
61-year-old Morsi, Egypt's first democratically elected president, was toppled by the military on July 3.
Morsi, who is facing criminal charges in many cases, was last seen in public on June 26 and has been detained along with senior aides of his Muslim Brotherhood party.
The Brotherhood's official website said at least 200 people had been killed and some 5,000 wounded, Ahram Online reported.
However, a health ministry official, Khaled El-Khatib, put the death toll from Friday and Saturday's clashes to 80.
Seventy-two of the casualties fell during violence between police and pro-Morsi supporters on the fringes of a month-long sit-in held by the president's loyalists in northern Cairo's Rabaa al-Adawia mosque, Ahram Online said.
Eight people were killed in Egypt's Mediterranean city of Alexandria during deadly clashes between pro and anti-Morsi supporters.
The official put the tally of injured at 792 nationwide, including 411 in clashes near the pro-Morsi sit-in in Cairo's Nasr City neighbourhood.
A spokesman from Morsi's Muslim Brotherhood said that more than 4,000 were wounded by tear gas and bullet or birdshot wounds in one of the bloodiest days in the nation.
The violence on Saturday was the bloodiest incident since Morsi's July 3 ouster
Meanwhile, Egypt's "Rebel" (Tamarod) campaign issued a statement on Sunday saying they are highly concerned with comments made by Minister of Interior Mohamed Ibrahim that they understood as foregrounding the possible return of the notorious Mubarak-era state security apparatus.
In a press conference held by the interior ministry on Saturday, Ibrahim announced that departments of state security tasked with fighting extremism and monitoring political and religious activity, terminated after the January 25 Revolution, have been reinstated
Ibrahim further added that a new police reshuffle will be announced on Monday and will include police officers who have been excluded before.
"Our campaign supports the state's plans in fighting terrorism; however, we have earlier stressed that this support doesn't include the taking of extraordinary measures, or the contradiction of freedoms and human rights," Mahmoud Badr, spokesman of the Rebel campaign, said in a statement.
During the ministry's press conference, which was held hours after deadly clashes between the police and supporters of deposed president Mohamed Morsi, Ibrahim attributed the occurrence of violence to the closing of the reinstated departments and the restructuring of the ministry in "a non-technical way" after the January 25 Revolution.
Saturday's killings followed a day of rival rallies.
The Grand Imam of Al-Azhar mosque -- the highest Sunni Muslim authority in Egypt -- has called for an investigation, while the vice-president of the interim government, Mohamed ElBaradei, has condemned the excessive use of force.
The bloodshed has thrown Egypt into deeper turmoil weeks.
The violence has claimed the lives of dozens and wounded hundreds since Morsi's ouster from the presidency.
The United States, Canada and the United Nations have called for calm and peace in Egypt amidst escalation of violence in the post populous Arab country.
Image: Supporters of Mohamed Morsi run from tear gas fired at them by police during clashes in Nasr city area.
Photograph: Asmaa Waguih/Reuters
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