| BENGHAZI, Libya
BENGHAZI, Libya East Libyan forces said they had regained control on Tuesday of the major oil ports of Ras Lanuf and Es Sider from a rival faction that seized them earlier this month and were pursuing their opponents into the desert.
Ahmed al-Mismari, spokesman for the eastern-based Libyan National Army (LNA), said fighters from the Benghazi Defence Brigades (BDB) were retreating toward the coastal town of Harawa, more than 100 km (60 miles) west of Es Sider and to Jufra, their desert base nearly 300 km to the south.
Air strikes were being carried out against BDB positions in Jufra late on Tuesday, an air force official said.
Footage and photos showed LNA troops posing around the ports, and a resident in Ras Lanuf confirmed that they had entered the town that adjoins the oil port and refinery following clashes and air strikes.
A statement by a media outlet aligned with the BDB said the group's fighters were still stationed in the area.
The fighting for control of the ports in Libya's Oil Crescent, a strip of coast southwest of Benghazi, has raised fears of an escalation of violence in the country and a reversal for the OPEC member state's efforts to revive its oil output.
The LNA and the BDB are on opposite sides in a stop-start conflict between factions based in eastern and western Libya that erupted in 2014, leaving Libya with rival governments.
Negotiations to strike a political deal between the two sides have so far failed, and the renewal of fighting could harden the east-west split.
Akram Buhaliqa, an LNA commander in the nearby city of Ajdabiya, said ground, air and naval forces had been deployed in Tuesday's offensive. The LNA said 10 of its troops had been killed and 18 wounded in the fighting. No casualty figures for the BDB were available.
The LNA took control of the Oil Crescent ports in September, ending a long blockade in the area. It handed the ports to the National Oil Corporation (NOC) in Tripoli, allowing it to more than double Libya's oil production.
The BDB's advance caught the LNA off guard and eastern factions reacted angrily, accusing a U.N.-backed government in Tripoli of supporting their rivals.
Mismari suggested that this time a handover to the NOC in Tripoli was not guaranteed, saying a decision on who would receive the ports would be made later and that the head of an eastern, breakaway NOC, Naji al-Maghrabi, would inspect them.
The statement came as a letter surfaced in which Maghrabi said he could no longer comply with a unification deal agreed last year with NOC Tripoli, partly because of the failure to move the NOC's headquarters to Benghazi.
Eastern factions have tried to sell oil independently of Tripoli in the past, but have been blocked by international sanctions that are still in place.
Since the BDB overran Es Sider and Ras Lanuf, Libya's national oil output has dipped again from about 700,000 barrels per day (bpd) to 600,000 bpd due to a disruption of operations at the ports.
The ports are two of the largest in Libya, with a combined potential capacity of about 600,000 bpd, but both were badly damaged in previous rounds of fighting and were operating at a fraction of pre-conflict levels.
The LNA retained control of Brega and Zueitina, the two ports closest to Benghazi.
The United Nations said on Tuesday the latest fighting around the Oil Crescent had been marked by human rights violations including unlawful killings and arbitrary detentions.
(Additional reporting by Ahmad Ghaddar in London and Aidan Lewis in Tunis; Editing by Gareth Jones, Toni Reinhold)