Syrian tanks enter demilitarized Israeli frontier - Article Photos 1/7

In this Friday, Nov. 02, 2012 photo, a sniper line-of-fire is seen through the scope of a rebel fighter's gun in the Karm al-Jebel neighborhood in Aleppo, Syria. U.N. officials and human rights groups believe President Bashar Assad's regime is responsible for the bulk of suspected war crimes in Syria's 19-month-old conflict, which began as a largely peaceful uprising but has transformed into a brutal civil war. However a video that appears to show a unit of Syrian rebels kicking terrified, captured soldiers and then executing them with machine guns raised concerns Friday about rebel brutality at a time when the United States is making its strongest push yet to forge an opposition movement it can work with. (AP Photo/Narciso Contreras)