At least nine security force members loyal to Libyan commander Khalifa Haftar and two civilians were killed by suspected Islamic State militants at a checkpoint in the central Jufra region, a military spokesman said.
A statement posted by Islamic State’s Amaq news agency said 21 of “Haftar’s militias” were killed or injured in the attack.
Haftar’s Libyan National Army (LNA) took over several strategic bases in Jufra and the neighbouring Sabha region earlier this year as rival factions withdrew.
“The terrorist organisation Daesh (Islamic State) attacked al-Fogha checkpoint in Jufra region, killing nine soldiers and two civilians were slaughtered,” said LNA spokesman Ahmed Mismari. He said the victims were beheaded.
Jufra is south of Sirte, the coastal city where Islamic State established a stronghold before being ousted by local forces late last year.
Some militants fled into the desert south and west of Sirte where Libyan officials say they have been trying to regroup.