The operation came just days after some militants from Al-Qaeda's Syria franchise, Nusra Front, pledged loyalty to ISIL in Albu Kamal, after it led an offensive in Iraq and seized chunks of territory.

But not all Nusra militants defected and those who refused to submit to the radical group joined forces with other militant groups to launch the counter-offensive.

According to the so-called Syrian Observatory for human rights fighting has raged since late last night in Albu Kamal between Nusra Front and other militant groups at one side and ISIL at the other.

ISIL and al-Nusra Front share same extremist views and both entered the war in Syria in 2011 with pledging loyalty to al-Qaeda leader Aymen Zawahiri.

Power struggles later caused ISIL to turn into an enemy, and al-Nusra became al-Qaeda’s representative in the Syrian war.

The background of the massive war in Syria which started in 2011, is marked with brutal executions and extremist acts of violence against civilians and Syrian soldiers, committed by al-Nusra and ISIL.

SHI/SHI