A fire from fuel tanks near Tripoli's international airport that has been ignited by rocket attacks is out of control as clashes between rival militias have resumed in the area, the National Oil Company says.
Six million litres of fuel were set ablaze by a rocket late on Sunday, with a second depot hit on Monday.
"It is out of control. The second tank has been hit and the firefighters have withdrawn from the site as the fighting has resumed in the area," National Oil Company spokesman Mohamed Al-Harrai told Reuters on Monday.
"The situation is very dangerous after a second fire broke out at another petroleum depot," the government said, warning of a "disaster with unforeseeable consequences".
The Libyan government earlier appealed for "international help" fighting the blaze amid heavy fighting that the Libyan government said has killed more than 150 people in Tripoli and Benghazi in two weeks.
A statement posted to the government's website on Monday warned of a "humanitarian and environmental disaster" after fighting between rival militias over the country's international airport caused the inferno.
Officials said that firefighters sent to the scene had been unable to put out the fire, AFP reported.
Al-Harrai said firefighters battled the blaze for hours before running out of water and being forced to leave.
As Libyan TV stations called on residents to evacuate areas near the aiport, social media sites posted images of black smoke billowing over Tripoli's skyline.
Earlier on Sunday, France, Britain, Germany, and Spain called on their nationals to leave Libya due to the deteriorating security situation.
The US, the UN, and Turkey have pulled their diplomats out of the North African country.
The US evacuated its embassy on Saturday, driving diplomats across the border into Tunisia under heavy military protection because of clashes near the embassy compound in Tripoli.
A British embassy convoy was hit by gunfire during what an embassy official described as "an attempted hijack" as the convoy was on its way to the Tunisian border. No one was injured in the incident.
Battle for airport
In Tripoli, 23 people, all Egyptian workers, were killed when a rocket hit their home on Saturday during fighting between rival militias battling over the city's main airport, the Egyptian state news agency reported.
Since the clashes erupted a fortnight ago, 94 people have died in the capital, and more than 400 have been injured as militias exchanged rocket and artillery fire across southern Tripoli, the Libyan health ministry said.
"Most of the victims we have noticed are civilians as the fighters have their own hospitals on the battlefield," a Benghazi medical source told Reuters news agency.
Another 55 people, mostly civilians, have been killed in Benghazi since the clashes intensified over the past week between regular forces and militias entrenched in the city.
A new Libyan parliament was elected in June and legislators are set to meet in August for the first session.