CAIRO, EGYPT - SEPTEMBER 14: An injured Egyptian is led away from clashes near the United States Embassy and  Tahrir Square on September 14, 2012 in Cairo, Egypt. Over two hundred people have been injured in clashes between protesters and security forces. Protests have continued into a fourth day in central Cairo, with Egyptians demonstrating against a US-made film said to be defaming the Prophet Mohammed, whose trailer had recently been released on Youtube and translated into Arabic. Egyptian authorities began construction of a concrete barrier early Friday morning to stop demonstrations planned across the country for Friday from reaching the US Embassy, after Egyptians demonstrated at the Embassy compound and breached its perimeter walls on Tuesday. (Photo by Ed Giles/Getty Images)