Thirty-six Libyan soldiers were killed and 70 wounded in clashes in Benghazi.
The killed soldiers belonged to brigades of general Khalifa Haftar.
A military source said Ansar al-Sharia forces attacked the Benina airport with three car bombings.
Libya is being racked by violence as the armed groups which helped topple Muammar Gaddafi in 2011 turn their guns on each other in a struggle for the country's vast oil resources and political domination.
The elected parliament has relocated to the remote eastern city of Tobruk after effectively losing control of the capital Tripoli, where an alliance of armed groups hold sway.
Source: MENA