The Libyan National Army (LNA) said on Friday they had killed a senior al-Qaeda figure in southern Libya, during an operation to secure oil and gas assets and fight militants in the south.

LNA spokesman Ahmed Mismari said they had killed Abu Talha al-Libi, a commander in al-Qaeda in the Islamic Maghreb (AQIM), and two other militants near the city of Sabha,

He named the others as Abdullah al-Desouki, an Egyptian, and al-Mahdi Dangou, a Libyan also known as Abu Barakat, who a Libyan official had previously said had links with ISIS.

Qaeda and ISIS have been using southern Libya as a base for attacks in Libya and neighboring countries, exploiting a security vacuum created by the overthrow of late ruler Muammar Gaddafi in a 2011 rebellion backed by NATO air strikes.

ISIS stepped up attacks in Libya, including the capital Tripoli, in recent months after regrouping in the south having lost its main base in the coastal city of Sirte in late 2016.

The LNA, which is led by Khalifa Haftar, sent troops to Sabha this week, triggering speculation they might be headed for the El Sharara oilfield, some 250 km (150 miles) away.

The 315,000-barrels a day El Sharara oilfield has been closed since December due to a protest by tribesmen and state guards demanding salary payments and development in the area.