Free Syrian Army
When ISIS first rose and took over Syrian land, the Free Syrian Army did not recognize ISIS as group against Assad, or work with the Islamic State. But sometimes, the Islamic state and the Free Syrian Army have helped each other during certain battles such as in the capture of Managh Air Base. According to the Syrian Observatory of Human Rights, either the Islamic State or Al-Qaeda detonated a Car bomb that killed 12 men. After the bomb hit, apparently missiles hit Syrian Army positions.