Article Photos: Video of police abuse stokes anger in Egypt 4/5

An Egyptian protester throws a tear gas canister back during clashes with riot police in front of the presidential palace in Cairo, Egypt, Friday, Feb. 1, 2013.  Thousands of protesters denouncing Egypt's Islamist president marched on his palace in Cairo on Friday, clashing with security forces firing tear gas and water cannons in the eighth day of the country's wave of political violence.(AP Photo/Khalil Hamra)