Cairo - The battle between rival militias for control of the Libyan capital raged amid increased fighting over the past the past 24 hours, officials said Saturday, with both sides relying heavily on air power to make progress in the stalemated conflict.

Forces loyal to Khalifa Haftar, a veteran army officer based in the country’s east, began an offensive to capture Tripoli in early April.

Haftar’s s Libyan National Army has been advancing into the city’s southern outskirts, clashing with an array of militias loosely affiliated with the government based in the capital.

Libyan officials, who spoke on condition of anonymity because they were not authorized to brief reporters, said Haftar’s LNA launched air strikes overnight against an air base in the western city of Misrata.

The officials said the LNA also took control of the Al Naqliyah military camp in the south of Tripoli.

They said Haftar’s forces were also fighting to cut off a major route linking Mistrata to Tripoli, which, if they succeeded, would be a major blow to the UN-supported government.

In past weeks, the battle lines have changed little, with both sides dug in and shelling one another in the southern reaches of the capital.

The LNA is the largest and best organised of the country’s many militias. But it has faced stiff resistance from fighters aligned with theTripoli government.

The Libyan officials said the LNA air strikes on the Air Force Academy in Misrata came after armed groups allied with Tripoli launched an air attack a day earlier against Al Jufra air base, the LNA’s main forward airfield in the Tripoli offensive.

The officials also said heavy fighting was underway in Abu Salim district, about 7km from Tripoli’s centre, and in Salah Al Deen, an area that saw previous clashes between rival militias in September.

The LNA’s media office said in a statement that over 10 air strikes had targeted a control room for Turkish-made drones, along with other targets in Misrata and the western coastal city of Sirte.

A spokesman for the Tripoli-based militias confirmed they had launched an air attack Friday against Al Jufra air base.

The LNA released a statement saying its forces had taken control of the Al Naqliyah military camp and advanced in different parts of southern Tripoli.