Al-Qaeda-linked militants in Syria have killed at least 50 rival insurgents amid continued infighting among militant groups. Opposition sources say the insurgents were killed in attacks, car bombings and summary executions by militants loyal to the Islamic State of Iraq and the Levant or I-S-I-L. Sunday\'s deaths came on the third day of infighting that began when militants of the so-called Free Syrian Army attacked checkpoints and bases manned by the I-S-I-L. The clashes have mostly centered in the northern provinces of Aleppo and Idlib. Opposition sources say the I-S-I-L militants summarily executed thirty of their civilian and non-civilian hostages after their base was surrounded by rival insurgents in the Harem district of Idlib province. Meanwhile, a group calling itself the Islamic Front, which is the biggest insurgent alliance in Syria, issued a strong warning to the ISIL militants, vowing to fight against the group. Show Less >>