BEIRUT - Al-Qaeda in Syria is fighting to drive rivals out of areas bordering Turkey and Iraq in a bid to control territory stretching from Iraq into northern Syria, various sources say.
Across the north and east, the Islamic State of Iraq and the Levant (ISIL) has set up checkpoints on roads to border crossings, and opened fronts to crush other rebel groups fighting to oust President Bashar al-Assad.
Residents have told AFP of a strategy that involves ISIL taking over resources and routes using brutal methods aimed at forcing the population into submission.
Analysts and activists on the ground have also noted the tactic.
"ISIL has been acting in such a way as to aggressively assert itself within the complex multi-dimensional insurgent theatres in northern and eastern Syria," said Charles Lister of IHS Jane's Terrorism and Insurgency Centre.
Jihadists have even sought to justify the strategy on Internet forums by accusing Western-backed groups, including Ahfad al-Rasul and the Northern Storm brigade, of acting like the US-funded "Sahwa" who fought Al-Qaeda in Iraq.