Death Toll Grows to 638 in Egypt Violence

World condemnation widened for the bloody crackdown on Morsi's mostly Islamist supporters, including an angry response from President Barack Obama, who canceled joint U.S.-Egyptian military maneuvers.

Violence spread on Thursday, with government buildings set afire near the pyramids, policemen gunned down and scores of Christian churches attacked. As turmoil engulfed the country, the Interior Ministry authorized the use of deadly force against protesters targeting police and state institutions.

The Muslim Brotherhood, trying to regroup after the assault on their encampments and the arrest of many of their leaders, called for a mass rally on Friday in a challenge to the government's declaration of a month-long state of emergency and a dusk-to-dawn curfew.

At least 638 people were confirmed killed and nearly 4,000 wounded in the violence sparked when riot police backed by armored vehicles, snipers and bulldozers smashed the two sit-ins in Cairo where Morsi's supporters had been camped out for six weeks to demand his reinstatement. It was the deadliest day by far since the 2011 popular uprising that overthrew autocratic ruler Hosni Mubarak and plunged the country into more than two years of instability.

Also on Thursday, The United Nations Security Council called on both the Egyptian government and the Muslim Brotherhood to exercise "maximum restraint" and end the violence spreading across the country. Council members called for national reconciliation.