Standoff in Cairo as Security Forces Surround Mosque Louafi Larbi/Reuters An Egyptian soldier stood guard near Fateh Mosque in Cairo's central Ramses Square, where supporters of the deposed president, Mohamed Morsi, were sheltering early Saturday. CAIRO - Soldiers, police officers and armed civilians surrounded a mosque where supporters of former President Mohamed Morsi were sheltering early Saturday, continuing a tense standoff between Islamists and the military-backed government a day after scores of people were killed in chaotic civil strife across the country. Riot police stood guard outside the Fateh Mosque in Cairo's central Ramses Square, which had been transformed into a field hospital and morgue on Friday during fierce clashes in the area. Tanks guarded the mosque's back entrance, and at about noon, witnesses said they heard gunfire. The standoff came as Mr. Morsi's supporters prepared for new demonstrations, raising the likelihood of further violence. Egyptian officials announced that they had arrested hundreds of Islamists over the last two days, as part of an expanding crackdown on the Muslim Brotherhood, Egypt's most powerful Islamist movement. The scenes outside the mosque, broadcast live on television on Saturday, deepened the sense that Egypt was descending into anarchy. On Friday, terrified protesters caught in a cross-fire jumped or fell from an overpass in a panicked effort to escape. A gunfight erupted on the doorstep of a Four Seasons hotel. Men wielding guns and machetes - some backing the Islamists, others police supporters in civilian clothes, others simply criminals - roamed the streets of the capital and other cities, and it was often impossible to tell friend from foe. News reports put the civilian death toll for Friday at well over 100, which would bring the total since Wednesday to nearly 750. Health Ministry officials said Friday's civilian toll was 27, but on Saturday, officials at a hospital near Ramses Square said that facility alone had received at least 52 bodies. Defying a 7 p.m. curfew, antagonists had battled into the night in the Ramses Square area Friday, lit by an unchecked fire that consumed a nearby office building. The military-appointed government issued a statement declaring that the military, the police and the people were "standing together in the face of the treacherous terrorist scheme against Egypt of the Brotherhood organization." But the extent of the mayhem cast doubt on its ability to deliver on its central promise of restoring order and security. France and Germany on Friday called for an emergency meeting of European foreign ministers to respond to Egypt's violence. "The toll of death and injury is shocking," said Catherine Aston, the top diplomat for the European Union. Responsibility for this tragedy weighs heavily on the interim government, as well as on the wider political leadership in the country. Just two days earlier, the police had routed thousands of protesters from sit-ins in support of Mr. Morsi, killing several hundred. The government suspended legal protections against arbitrary police action and authorized security forces to kill anyone who threatened a public facility. For many on Friday, however, shock at the scale of the bloodshed began to outweigh the threats. The violence started soon after noon prayers, as thousands of Islamists marched in a last defense against a return to the era of political exclusion, imprisonment and torture they endured under 60 years of military-backed dictatorship. For the first time since the president's removal six weeks ago, some non-Islamists stood with the Morsi supporters, sometimes risking their own lives as well. "Where are we going with this?" one young man asked another watching at the edge of the Ramses Square battle. Are we just going to fight one another endlessly? His friend replied that he had protested against President Morsi, and that the police had protected him from threats. But now they were killing the Islamists, he said. "They're Egyptian, too," he said. Why were we safe while they're being killed by the police?