Muammar Gaddafi loyalists attacked an oil refinery on Monday, killing 15 guards, in an apparent attempt to disrupt a drive by Libya's new rulers to seize the ousted leader's last bastions and revive the oil-based economy, Reuters reported.
Witnesses said the assailants damaged the front gate of the refinery, 20 km (13 miles) from the coastal town of Ras Lanuf, but not the plant itself, which is not fully operational.
About 60 staff were at the refinery at the time of the attack, according to one of two wounded survivors at a hospital where the dead were also taken. Blood stained the floor.
Refinery worker Ramadan Abdel Qader, who had been shot in the foot, told Reuters gunmen in 14 or 15 trucks had come from the direction of the Gaddafi-held coastal city of Sirte.
"We heard firing and shelling at around 9 in the morning from Gaddafi loyalists," he said. Staff had been asleep.
The assault occurred only hours after Libya's National Transitional Council (NTC) announced that it had resumed some oil production, which had been all but halted since anti-Gaddafi protests turned into civil war in March.
NTC forces, which seized Tripoli on August 23, said they were meeting fierce resistance on the fourth day of fighting for the Gaddafi-held desert town of Bani Walid, 150 km (95 miles) southeast of the capital, but were edging toward Sirte.
As pressure builds on Gaddafi's last strongholds, some of his top officials and family members have fled abroad -- including his son Saadi, who arrived in neighboring Niger on Sunday after crossing the remote Sahara desert frontier.
The NTC has said it will send a delegation to Niger to seek the return of anyone wanted for crimes, but Jalal al-Galal, a council spokesman, said the visit had not yet been scheduled.
"We want to take the necessary legal steps to give us possibility of obtaining the detention and extradition of anyone we are seeking," he said, adding that time was needed to prepare the paperwork to satisfy international legal norms.