TRIPOLI, Aug. 22 (Xinhua) -- Clashes between forces of Libya's UN-backed government and the eastern-based army on Wednesday killed 13 people and injured dozens south of the capital Tripoli, military sources said Thursday.

"Seven of our troops were killed in battles to control parts of southern Tripoli," Mustafa al-Mejii, spokesman of the UN-backed government's forces, told Xinhua on Thursday.

The spokesman confirmed that the UN-backed government's forces remained in their positions despite attacks of the eastern-based army in the area.

A source of the eastern-based army said that its six soldiers were killed and dozens were injured in battles against the UN-backed government's forces.

The source confirmed that the eastern-based army's fighter jets attacked the UN-backed government's forces in southern Tripoli, causing significant losses of equipment and troops.

The UN-backed government has been engaged in a deadly armed conflict since early April in and around the capital Tripoli against the eastern-based army, which is trying to take over the city and overthrow the UN-backed government.

The eastern-based army, led by Khalifa Haftar, is allied with the eastern-based government, as the Libya is politically divided between eastern and western governments.

Libya has been struggling to make a democratic transition amid insecurity and chaos ever since the fall of former leader Muammar Gaddafi in 2011.