Plainclothes policemen throw stones from the top of a cabinet

Plainclothes policemen throw stones from the top of a cabinet building during clashes with protesters near Tahrir Square in Cairo December 16, 2011. At least two people were killed and 100 wounded in Cairo on Friday as demonstrators fought troops in the worst violence since Egypt began its first free election in six decades. In a pattern that has recurred during nine months of army rule since President Hosni Mubarak's overthrow in February, the confrontation swiftly grew as more people took to the streets.