Egypt\'s security forces acted with \"self-restraint\" in clearing sit-ins by backers of ousted President Mohamed Morsi, the military-led interim government said. At the same time, Islamist protesters removed in a bloody crackdown from two sit-ins established new sit-in sites overnight -- one outside a landmark Cairo mosque and others in cities around the country, The New York Times reported. Their sit-ins defied a new 7 p.m. to 6 a.m. curfew and the interior minister\'s vows to break up any such assemblies. \"Our forces have exercised self-restraint and professionalism in their actions,\" the government said in a statement read on state television Wednesday night. \"This is reflected in the low number of injuries.\" At least 278 people were killed and more than 2,000 wounded, the Interior Ministry said, in Egypt\'s deadliest day since the 2011 uprising that toppled autocratic President Hosni Mubarak. Of the dead, 235 people were civilians and 43 were police officers, Interior Minister Mohammed Ibrahim said. Also killed were at least two journalists, including a British cameraman for Britain\'s Sky News network. The Muslim Brotherhood, which backed the protests, said more than 2,000 people died in the violence. A spokesman for the Brotherhood\'s political arm called the dawn crackdown a \"massacre.\" Hundreds of Morsi-allied Muslim Brotherhood members were arrested nationwide Wednesday, the government said. Mohamed ElBaradei, the Nobel Peace Prize winner and vice president, resigned Wednesday in protest over the bloody crackdown. The Obama administration strongly condemned the violence and said it would hold the interim government accountable for its promises of a speedy transition to a democratically elected civilian administration. Ibrahim, one of the few ministers who kept his Cabinet post after Morsi was ousted July 3, said in a televised address Wednesday night his security forces \"insisted on maintaining the highest degrees of self-restraint.\" Interim Prime Minister Hazem al-Beblawi, a Western-trained economist who had been considered a liberal, echoed Ibrahim\'s remarks, saying in a televised statement security forces acted with the utmost \"self-restraint\" after six weeks of the unauthorized sit-ins. He cited the Islamist protesters\' alleged stockpiling of weapons and ammunition in justifying the use of force, which he said was intended to protect the rights of other citizens. \"Things were spiraling out of control, and we decided to take a firm stance,\" he said.