Oil security forces said on Friday they had retaken control of Libya's al-Ghani oilfield after gunmen attacked the facility, killing seven guards.
The official, Ali Hassi, said his forces were also now in control of Mabrouk, Bahi and Dahra oilfields in the central Sirte basin, which were reportedly attacked by Islamists over the last week.
"Our forces have taken back control of al-Ghani oilfield from militants. Unfortunately seven members of our forces were killed," Hassi said.
Libya's two rival governments and their armed forces have been battling for control of the North African country's oil infrastructure. Islamist militants have also gained ground, four years after a NATO-backed civil war ousted Muammar Gaddafi.
Rival factions this week held United Nations backed talks in Morocco in an effort to form a unified government and end a conflict Western officials fear will spiral into a full-blown civil war.
The internationally-recognized government of Prime Minister Abdullah al-Thinni has operated out of the east since a rival armed faction called Libya Dawn took over Tripoli last summer and set up its own administration.
With the rival governments both claiming legitimate control over oil operations, details about attacks, oil shipments and even production can be difficult to verify.
Hassi, who is allied with Thinni's eastern government, said security forces had not entered yet because mines had been laid in the fields. Several militants had been killed during the clashes and the fields had been damaged, he said.
Fighting between the rival governments has closed two major export terminals since December and slashed the state's crude output to less than half of the 1.6 million barrels per day produced in the Gaddafi era.
Islamist militants have been blamed for overrunning the Bahi and Mabrouk fields. Dahra has also been the site of clashes between Islamist militants and oil security forces.
Libya declared force majeure on 11 oilfields in its central region earlier this week after halting production there because of deteriorating security.
Last month, gunmen killed 12 people south of Sirte, among them two Filipino and two Ghanaian nationals, after storming a remote oilfield. Officials said most of the victims were beheaded or shot.
REUTERS