In this photo taken Tuesday, Feb. 17, 2015, a thermal camera sits atop a post at the Serbian border with Hungary close to Hajdukovo, 150 kilometers north of Belgrade, Serbia. (AP Photo/Marko Drobnjakovic)
In this photo taken Tuesday, Feb. 17, 2015, a thermal camera sits atop a post at the Serbian border with Hungary close to Hajdukovo, 150 kilometers north of Belgrade, Serbia. (AP Photo/Marko Drobnjakovic)
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