A Pakistani female health worker visits Lahore's slums to administer the polio vaccine to infants on Wednesday, Dec. 19, 2012 in Pakistan. Gunmen shot dead a woman working on U.N.-backed polio ... more 
A Pakistani female health worker visits Lahore's slums to administer the polio vaccine to infants on Wednesday, Dec. 19, 2012 in Pakistan. Gunmen shot dead a woman working on U.N.-backed polio vaccination efforts and her driver in northwestern Pakistan on Wednesday, officials said, raising the number of people killed in the last 48 hours who were part of the immunization drive. (AP Photo/K.M. Chaudary) less 
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Associated Press | Photo By K.M. Chaudary
Thu, Dec 20, 2012 2:53 AM EST