EDITORS PLEASE NOTE: CONTAINS GRAPHIC CONTENT<br/> <br />ROUGH CUT (NO REPORTER NARRATION)<br/> <br />Two car bombs hit a rebel-held border post in the northwest Syrian province of Idlib on Monday (January 20), opposition activists and fighters said, killing at least 16 people and closing the frontier.<br/> <br />The Bab al-Hawa crossing is held by a rebel alliance called the Islamic Front, which have been fighting with the al Qaeda-linked Islamic State in Iraq and the Levant (ISIL), a small but powerful affiliate of al Qaeda with a core of foreign fighters.<br/> <br />Amateur video posted on the Internet appeared to show the aftermath of the attack, with bodies on the ground near burning wreckage.<br/> <br />It was not immediately clear who planted the bombs. The attack occurred a few days after a car bomb that killed 26 in the eastern city of Jarablus and which activists blamed on ISIL.<br/> <br />The infighting has sparked the bloodiest internecine clashes in the history of Syria's nearly 3-year-old uprising, wi
