An anti-Mursi protester uses his sandal to beat a crossed-out picture of President Mohamed Mursi during an anti-Mursi and anti-Muslim Brotherhood protest in Tahrir square in Cairo June 28, 2013. Egypt's leading religious authority warned of "civil war" on Friday and called for calm after a member of the ruling Muslim Brotherhood was killed ahead of mass rallies aimed at forcing the president to quit. REUTERSAsmaa Waguih (EGYPT - Tags: POLITICS CIVIL UNREST)