Opposition protesters run to cover after being fired upon by police during an opposition march in Riffa, Bahrain, south of the capital Manama on March 11, 2011. Bahraini anti-riot police clashed with opposition protesters on the outskirts of Riffa after pro-government supporters were able to pass through police lines and attack the opposition march. Nearly 800 people were injured according to the health ministry, mainly due to tear-gas inhalation. UPI/Isa Ebrahim