Rival Libyan forces carried out tit-for-tat airstrikes on oil terminals and an airport on Tuesday, escalating their battle for control of the country days before United Nations peace talks were due in Morocco.
The OPEC oil producer's oil installations and other key infrastructure are increasingly a target in the conflict which pits two rival governments and their armed forces against each other, nearly four years after the ousting of Muammar Gaddafi.
Prime Minister Abdullah al-Thinni's internationally recognised government and elected parliament have been operating from the east since rival Libya Dawn forces took over Tripoli in the summer and set up their own administration.
A warplane belonging to Tripoli-allied forces bombed the oil ports of Ras Lanuf and Es Sidra, causing only minor damage, according to a security official with Thinni's government.
"They targeted the civil airport in Ras Lanuf, and oil tanks in Es Sidra. The rockets fell near the tanks, resulting in only minor damage," said Ali Hassi, a spokesman for the forces guarding Libya's oil infrastructure.
Es Sidra and Ras Lanuf, which make up half of Libya's oil output when operating normally, shut down in December due to the conflict. Libya currently produces around 400,000 barrels of oil per day, compared to 1.6 million bpd before Gaddafi was toppled.
Warplanes also hit Maitiga, Tripoli's airport, air force commander Saqir El-Jaroshi said, and there were plans to carry out air strikes on the airport of port city Misrata, which is also a base of Libya Dawn.
Jaroshi said the strikes were retaliation for Tripoli forces bombing Zintan, a town loyal to Thinni's government, and also to stop supplies to the militants.
A source at Maitiga said a warplane struck close to the runway but did not cause major damage. Most international airlines stopped flying to Libya and foreign diplomats were pulled out as fighting worsened last year.
Islamist militants in Libya claiming ties to Islamic State in Iraq and Syria have carried out high profile attacks which have raised fears the country has become a haven for extremists, just across the Mediterranean from mainland Europe.
A spokesman for the Tripoli-allied forces did not immediately respond to a request to confirm the attack on the oil ports or on Tripoli.
Western governments are backing United Nations efforts to bring the two sides together to form a unity government, broker a ceasefire and to put Libya's fragile transition to democracy back on track.
A delegate for the Tripoli administration said on Monday the U.N. sponsored talks, seen by some as the only chance to end the turmoil, are due to resume on Thursday although a UN spokesman could not immediately confirm the date.