Masked Gunmen Firing at Egyptian Protesters

Clashes continue ahead of a constitutional referendum

Masked gunmen have fired at protesters camping in the Egyptian capital, wounding nine people as supporters and opponents of President Mohamed Morsi prepare for rival mass rallies.

Officials and witnesses say the unknown gunmen shot the protesters in Cairo's Tahrir Square early Tuesday.  By midday the square was calm, with tents remaining in the center and the number of people in the area slowly growing.