Sixteen people, most of them soldiers, were killed and 81 injured in clashes between the Libyan army and Islamist fighters in the eastern city of Benghazi, medical and military sources told AFP Tuesday.
"Most of the dead and injured are soldiers. Three civilians, including an Egyptian, were killed when a rocket hit their house," a hospital source said on condition of anonymity.
A military official said fighting broke out after an alliance of Islamist militia attacked an army barrack, killing five soldiers.
Special forces soldiers violently battled the Islamists, who have held sway in Benghazi since a 2011 revolution which ousted and killed longtime dictator Moamer Kadhafi, plunging the nation into turmoil.
Near-daily clashes take place in Libya's second city between the army and various Islamist groups, including Ansar al-Sharia, which has been classified by Washington as a terrorist organisation.
Renegade former general Khalifa Haftar launched an offensive against Islamist militias in Benghazi in May.
Authorities in Tripoli accuse his "National Army" paramilitary force of trying to mount a coup.
Libya has been awash with weapons since the uprising three years ago that toppled and killed Kadhafi, and successive interim governments have struggled to establish a strong army and police force, giving former rebel groups a free hand to act.
Rival militias have been engaged in a bloody battle for Libya's main international airport in Tripoli for 10 days that has halted all flights and caused extensive damage to airport infrastructure.
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