TRIPOLI, July 16 (Xinhua) -- The Health Ministry of Libya's UN-backed government on Tuesday said that four people have been injured when an airstrike hit a field hospital in south of the capital Tripoli.

"The field hospital in Asswani area (southern Tripoli) has been attacked by an airstrike, injuring three ambulance drivers and a paramedic," the ministry said in a statement.

The ministry condemned the "unethical direct targeting of the hospital," adding that the strike caused great damage to the hospital.

"This is the second time the field hospital in Asswani area were attacked, despite the fact that the hospital is located away from the conflict areas," said the ministry's Head of Emergency and Crisis Department Fawzi Wanis.

The eastern-based army has been leading a military campaign since early April to take over Tripoli from the government.

According to the World Health Organization (WHO), the fighting has so far killed more than 1,000 people and injured more than 5,700 others, while more than 100,000 have fled their homes because of the armed conflict.

Libya has been suffering escalating violence and political instability ever since the fall of the late leader Muammar Gaddafi's regime in 2011.