Protesters opposing Egyptian president Mohamed Mursi try to hide from firing from riot policemen along Kasr El Nile bridge, which leads to Tahrir square, in Cairo January 29, 2013. Egypt's army chief said political unrest was pushing the state to the brink of collapse - a stark warning from the institution that ran the country until last year as Cairo's first freely elected leader struggles to curb bloody street violence. REUTERS/Mohamed Abd El Ghany (EGYPT - Tags: POLITICS CIVIL UNREST)