SANAA, Yemen — Forces loyal to Yemen's embattled president opened fire at protesters demanding his ouster across the country Monday, killing two demonstrators at two separate rallies and wounding at least 10 people at a third protest, activists said.The latest violence came as a Gulf Arab proposal for President Ali Abdullah Saleh to step down appears increasingly doomed, raising prospects of more bloodshed and instability in a nation already beset by deep poverty and conflict.Read More... More on Middle East Protests