At least nine soldiers lost their lives on Saturday in South Libya’s attack claimed by Islamic State on a training camp belonging to the eastern Libyan forces of Khalifa Haftar, hospital authorities said.

The attack, according to Reuters took place in the city of Sebha, located in part of the oil-producing south that is targeted by armed groups looking to exploit a security void.

Haftar has concentrated his forces in the northwest, where they have been embroiled for the past month in a battle for the capital Tripoli with fighters allied to the divided country’s internationally recognised government.

Reports have it that clashes raged in Tripoli’s southern outskirts throughout the night with the rival forces firing at each other with artillery guns, residents said. No more details were immediately available.

Islamic State claimed the Sebha attack. Its fighters had killed or wounded 16 and freed inmates from a prison, the jihadist group said in a statement posted online.

A military source said a jail inside the attacked Jabril Baba camp had been stormed but gave no details. Sebha hospital put the number of dead at nine, a statement on its website said.

Hamed al-Khaiyali, head of the local municipality, earlier told Reuters that one soldier had been beheaded and seven others “slaughtered” or shot.

A source in Haftar’s Libyan National Army (LNA) blamed Islamic State and Chadian fighters for the attack, the latter a term used by the LNA for tribesmen opposing Haftar.

News-gathering in southern Libya is difficult due to the absence of an effective state authority in a region dominated by different armed groups and tribes.

Islamic State is active in the south to where it retreated after losing its stronghold in the central city of Sirte in December 2016.

There have been several attacks in southern Libya since the Tripoli offensive, among them an assault on the Tamanhint air base outside Sebha and clashes at the El Sharara oilfield, the country’s biggest.

As well as the humanitarian cost, the Libya conflict threatens to disrupt oil supplies, boost migration to Europe and has scuppered a U.N. peace plan to hold elections to produce a unified government and army.