DEVELOPMENTS

• The Obama administration signaled Monday that U.S. national security interests will trump its promotion of Egypt’s budding democracy, stressing the importance of continued aid to the Egyptian military, which overthrew the elected president last week. But if the American government makes a legal determination that the removal was done through a coup d’etat, U.S. law would require ending all non-humanitarian aid to Egypt, the vast majority of which goes to the military. Administration officials said lawyers were still reviewing developments to make that ruling.

• Egypt on Monday restricted the ability of Syrians to enter the countryy, with officials citing reports that a large number of Syrians were backing the Muslim Brotherhood. The decision dealt a blow to Syria’s main Western-backed opposition group that is leading the fight against President Bashar Assad from its headquarters in Cairo.

ASSOCIATED PRESS

More than 50 supporters of Egypt’s ousted president were killed by security forces Monday in one of the deadliest single episodes of violence in more than 2 ½ years of turmoil. The toppled leader’s Muslim Brotherhood called for an uprising, accusing troops of gunning down protesters, while the military blamed armed Islamists for provoking its forces.

The early morning carnage at a sit-in by Islamists outside the Republican Guard headquarters, where ousted President Mohammed Morsi was first held last week, further entrenched the battle lines between Morsi supporters and his opponents. The uproar weakened the political coalition that backed the military’s removal of the country’s first freely elected leader.

Egypt’s top Muslim cleric, Sheik Ahmed el-Tayeb, the grand imam of Al-Azhar, warned of civil war and took the unusual step of announcing he would seclude himself in his home until the two sides “stop the bloodshed.”

The sole Islamist faction that backed Morsi’s removal, the ultraconservative Al-Nour Party, suspended its participation in talks on forming a new leadership for the country. The group is now torn by pressure from many in its base, furious over what they saw as a “massacre” against Islamists.

Both the military and the Brotherhood appeared determined not to back down in the confrontation. The Brotherhood accuses the military of carrying out a coup against democracy, while their opponents say Morsi squandered his 2012 election mandate and was leading the country into a Brotherhood monopoly on power.

The military-backed interim president announced a fast-track timetable that would lead to elections for a new parliament within about seven months.

Under the plan, two panels would be appointed to make amendments to the Islamist-drafted constitution passed under Morsi. Those changes would be put to a referendum within about 4 1/2 months. Parliamentary elections would be held within two months, and once the new parliament convenes it would have a week to set a date for a presidential election.

The swift issuing of the plan reflected a drive to push ahead with a post-Morsi political plan despite Islamist rejection — and is likely to further outrage the Brotherhood.

Immediately, both sides presented their versions of what happened at the protest site, where about 1,000 Morsi supporters had been camped out for days in the streets around a Mosque near the Republican Guard Headquarters. After the violence began around dawn, the two sides battled it out for about three hours.

Protesters and the Brotherhood said it began when troops descended on them and opened fire unprovoked as they finished dawn prayers.

Spokesmen for the military and police, however, gave a nationally televised news conference saying gunmen among the protesters sparked the battle.

Army Col. Ahmed Mohammed Ali said police and troops guarding the Republican Guard complex came under “heavy gunfire” about 4 a.m., and attackers on rooftops opened fire with guns and molotov cocktails. A soldier and two policemen were killed, and 42 in the security forces were wounded, eight critically, he said.

While he said troops had a right to defend the facility, however, Ali did not directly explain how the protester deaths occurred. He expressed condolences but offered no apologies for the deaths.

Several witnesses from outside the protest said the gunfire started when troops appeared to move on the camp.

University student Mirna el-Helbawi said she watched from her 14th floor apartment overlooking the scene, after she heard protesters banging on metal barricades, a common battle cry. El-Helbawi, 21, said she saw troops and police approaching the protesters, who were lined up on the street behind a make-shift wall. The troops fired tear gas, the protesters responded with rocks, she said.

Soon after, she heard the first gunshots and saw the troops initially retreat backward — which she said led her to believe the shots came from the protester side. She saw Morsi supporters firing from rooftops, while the troops were also shooting.

By the end, at least 51 protesters were killed and 435 wounded, most from live ammunition and birdshot, emergency services chief Mohammed Sultan, according to the state news agency.

El-Tayeb’s announcement he was going into seclusion was a symbolic but dramatic stance — a figure seen as a moral compass by many Egyptians expressing his disgust with all sides in the events. Egypt’s Coptic popes have at times gone into seclusion to protest acts against the Christian community, but the sheik of Al-Azhar has never done so.