TRIPOLI, April 12 (Xinhua) -- Air force of the eastern-based Libyan army on Friday attacked military camps of the UN-backed government in the capital Tripoli and the western city of Zuwara.

A fighter jet attacked a military camp in the eastern suburbs of Tripoli, targeting a number of military vehicles, Khaled Dardur, an officer of the camp, told Xinhua.

The officer confirmed that the attack was carried out by the eastern-based army, adding that the attack caused no human casualties.

Hundreds of people in Tripoli protested against the ongoing fighting between the UN-backed government's forces and the eastern-based army on Friday.

Moreover, another fighter jet of the army attacked a military camp in Zuwara, some 120 km west of Tripoli.

According to the local TV channel Libya Al-Ahrar, the attack injured a civilian nearby.

Last week, the army launched a military campaign to take over the capital where the UN-backed government is based.

The World Health Organization on Thursday said the fighting killed 56 people and injured 226 others so far.

The army is allied with the eastern-based government, as the country is politically divided between western and eastern governments.

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