Empty bullet cases lie on the ground as camera operators film a crime scene where members of the Mexican army were ambushed by gunmen in Guachinango May 12, 2014. A military truck and a car were burnt... more 
Empty bullet cases lie on the ground as camera operators film a crime scene where members of the Mexican army were ambushed by gunmen in Guachinango May 12, 2014. A military truck and a car were burnt and at least four soldiers killed in the attack, according to local media. Picture taken May 12, 2014 REUTERS/Alejandro Acosta (MEXICO - Tags: CRIME LAW CIVIL UNREST MILITARY TPX IMAGES OF THE DAY) less 
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Reuters | Photo By STRINGER / REUTERS
Tue, May 13, 2014 10:58 PM EDT