The Free Syrian Army and the Islamic Front claimed to have gained control over the northern town of Addana on Friday (January 10) from the Islamic State of Iraq and the Levant.
The town, located 40 km north of Idlib, has been under the control of the Islamic State, which is an Al Qaeda affiliate led by foreign jihadists, for the past nine months.
"The Islamic Front gained control over the courts and of various checkpoints." said an unnamed rebel from the Islamic Front.
The Islamic Front and the Free Syrian Army placed the town under siege for four days before being able to gain control of important checkpoints and the court in the town.
Syria's rebel movement has been a constantly shifting array of groups and alliances since the uprising against President Bashar al-Assad began nearly three years ago.
Assad's security crackdown transformed Syria's largely peaceful protest movement in March 2011 into an armed insurgency in the first year of the revolt, and since then opposition formations have been increasingly overtaken by Islamist groups.
As new leaders have emerged within the opposition, infighting intensified and reached a new level this month, with several rebel factions declaring war against the radical Islamic State of Iraq and the Levant (ISIL).