A explosives disposal expert wearing a protective suit walks near US Airways on the tarmac at Philadelphia International Airport Friday, Aug. 5, 2011, in Philadelphia. Passengers aboard a US Airways ... more 
A explosives disposal expert wearing a protective suit walks near US Airways on the tarmac at Philadelphia International Airport Friday, Aug. 5, 2011, in Philadelphia. Passengers aboard a US Airways flight that flew in from Scotland were removed and the plane taken to another part of Philadelphia International Airport because of an unspecified threat on Friday. (AP Photo/Alex Brandon) less 
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Associated Press | Photo By Alex Brandon
Fri, Aug 5, 2011 7:02 PM EDT