A recent suicide bombing in southern Syria shows the rivalry between Al Qaeda and ISIS is more than just a contest to see who can kill the most infidels -- the groups are using classic terror techniques on each other. The Nov. 15 bombing came at a top-level meeting of the Yarmouk Martyrs Brigade, a key ISIS militia known for its bloody and vicious hold over parts of the Golan Heights. Six of the group’s top men were killed, including Muhammad "Abu Ali" al-Baridi, the shadowy head of the group who went by the nickname “The Uncle.” Al Nusra Front, Al Qaeda’s Syrian affiliate, quickly took credit, gloating on Twitter about the “heroic” attack. “The Islamic State [ISIS], that controls the closest area to the Israel border in the Syrian Golan Heights, suffered a severe blow and lost its entire top command in the area in one fell swoop,” noted Alex Fishman, a veteran military correspondent for Israeli daily Yediot Aharonot. "ISIS ... suffered a severe blow and lost its entire top command in the area in one fell swoop.” - Alex Fishman, Yediot Aharonot While ISIS and Al Nusra fight common enemies as well as each other north of Damascus, the two terror groups are in an all-out war south of the capital, along the Israeli border. It is in that part of the hugely complex Syrian conflict where the bitter infighting between the Sunni Muslim terrorist groups is most deadly and direct. ISIS has largely captured the international spotlight from Al Qaeda, the group from which it sprang, with mass executions, gruesome beheadings and even the apparent use of chemical weapons. But while the black-clad killers have sown fear across the globe, the organization behind the infamous 9/11, 7/7, and countless other major atrocities, is not surrendering its longtime perch atop the terror heap. Word of the suicide bombing trickled out slowly, in part because the world’s eyes were on Paris, where an ISIS attack left 130 dead on Nov. 13. Regional Arab media first indicated that ISIS in Syria received the stunning blow in the Golan Heights village of Jamleh. When news got out about the death of the terrorist known as “The Uncle,” who earlier this year posted a video on social media pledging his allegiance to ISIS, the devastating blow to ISIS was revealed.