Eastern Libyan forces loyal to commander Khalifa Haftar carried out four air strikes near the El Feel oilfield, a field engineer told Reuters on Feb. 9.
The strikes were warnings directed at rival commander Ali Kennah who was inside the compound at the time of the strikes, he said.
But Libya's Government of National Accord (GNA), backed by the United Nations, said in a statement that the strike targeted a civilian plane that was trying to evacuate a number of wounded people from the oilfield to Tripoli.
The strikes damaged the oilfield's infrastructure and its airport runway and "put civilian lives at risk", the statement added, without adding details of any casualties.
Haftar is a dominant figure in eastern Libya where his Libyan National Army group seized the second-largest city of Benghazi in 2017 by expelling Islamists and other fighters.
Last month, his forces started an offensive in the south to fight militants and secure its oilfields, and on Wednesday made good on the promise by moving on the closed El Sharara field.
Kennah, the commander of the Sabha military zone who served under former dictator Muammar Gaddafi, was appointed by Prime Minister Fayez Seraj last week. Fayez leads the internationally-recognised government based in Tripoli.
Libya's oil industry has faced disruption since unrest began, with rival power centres in the west and east.
El Feel, which usually pumps around 70,000 barrels per day, was shut down when the larger El Sharara oilfield was seized and closed by tribesmen and state security guards in December.
The parties must now renegotiate a deal that would transfer Breitburn's Permian reserves to investors including Elliott and WL Ross through their participation in a $775 million rights offering.
Sustained lower oil prices may lead to Permian consolidation, the return of tough times to other shale plays and U.S. E&Ps helping rebalance global inventories.
A big crowd turned out for an afternoon honoring industry leaders representing all facets of the energy sector.