Al Qaeda-Linked Group in Syria Tightening Grip in North of the Country

Islamic State of Iraq and Syria (ISIS)

Gaziantep, Turkey (CNN)—Al Qaeda has swept to power with the aim of imposing a strict Islamist ideology on Syrians across large swathes of Syria's rebel-held north, according to a CNN survey of towns, activists and analysts that reveals an alarming increase in al Qaeda-linked control in just the past month.

Al Qaeda-backed militants known as the Islamic State of Iraq and Syria (ISIS) are the predominant military force in northern Syria, according to activists and seasoned observers, and have a powerful influence over the majority of population centers in the rebel-held north.