By Ayman al-Warfalli
BENGHAZI, Libya (Reuters) - A fire caused by fighting at one of Libya's main export terminals has destroyed more than two days of the country's oil production, officials said on Sunday, as clashes escalated between factions battling for control of the OPEC member nation.
A missile hit an oil storage tank last week at the port of Es Sider during fighting between forces allied to Libya's two competing governments and the resulting blaze has destroyed 800,000 barrels of crude, the National Oil Corporation said.
In an apparent response to the attack on Es Sider, forces loyal to Libya's recognised government -- now based in the east after being forced to flee Tripoli in the summer -- staged air strikes on targets in the western city of Misrata on Sunday.
The raids were the first such attacks on a city allied to the militia group that seized Tripoli, and whose forces have been trying to take the eastern oil ports from the internationally recognised government, officials and residents said.
Libya has been engulfed in fighting between the two sides, each with its own government and parliament and each anxious to secure a share of Africa's largest oil reserves.
The internationally recognised Prime Minister Abdullah al-Thinni has been forced to run a rump state in the east since the Libya Dawn group took control of Tripoli in August, setting up a rival government and parliament.
Es Sider and the adjacent Ras Lanuf terminal have been closed since a force allied to Libya Dawn moved east from the capital two weeks ago in an attempt to seize the facilities.
An NOC spokesman said three oil storage tanks at Es Sider were still on fire on Sunday, while firefighters had managed to extinguish the blaze at three other tanks.
Libya's total oil production stands at 385,000 barrels per day, the NOC said.
NOC added that natural gas exports from its Mellitah joint venture with Italian energy giant Eni (MI:ENI) have fallen to 60 percent of the western port's capacity.
NOC says fighting and the shutdown of gas fields linked to Es Sider have forced it to use some of Mellitah's output for domestic consumption.
Mohamed El Hejazi, spokesman for armed forces loyal to Prime Minister Thinni, said his air force had attacked Misrata's port, an air force academy near the airport and Libya's biggest steel plant, which is located in the city.
Ismail Shukri, spokesman for forces allied to Libya Dawn, confirmed that air strikes had taken place but said they caused no damage.
"The airport at Misrata is still working normally. A flight has just taken off," he said.
Misrata, 200 km (125 miles) east of Tripoli, is linked to Libya Dawn and home to a major sea port and free trade zone.The city had so far escaped the fighting that has threatened to break up Libya.
Since Muammar Gaddafi was ousted in 2011, Libya has failed to attain stability. Former rebel brigades which once fought side by side have now turned on each other, aligning themselves with rival political factions in a scramble for control.
(Additional reporting by Ahmed Elumami; writing by Ulf Laessing; editing by Giles Elgood)