Forces allied to Libya’s eastern government carried out an air strike against a military transport aircraft in the central district of Jufra on Tuesday, wounding the head of the military council from the rival city of Misrata, officials said.

The strike, and clashes that preceded it on Monday, raised fears of an escalation in Libya’s central desert region between the country’s two main military power bases.

Tension has been building in the area between the eastern-based Libyan National Army (LNA) led by Khalifa Haftar, and forces either from or linked to the western port city of Misrata, some aligned to the UN-backed government.

The two sides were in opposing military alliances that fought for control of Tripoli in 2014, leaving Libya with two competing governments.

On Tuesday, the LNA said one of its fighter jets had struck a C-130 transport plane parked in Jufra that a senior LNA source said was delivering arms and ammunition to what it called terrorist groups based there.

The LNA has carried out previous strikes nearby against forces including Islamist fighters that it says have been mobilising to try to retake several LNA-held ports in the so-called “oil crescent” along the coast.

But an air force spokesman in Misrata, Mohamed Gnounou, said the C-130 was carrying a visiting delegation from Misrata, confirming that the head of the city’s military council, Ibrahim Baitulmal, had been wounded. One person was killed in the strike, and a third person wounded, he said.

Gnounou said he was speaking on behalf of forces allied to the UN-backed Government of National Accord (GNA) in Tripoli.

“We, the emergency operations room of air forces of the GNA consider this a criminal act. However, in the interests of Libyans, we will respond wisely,” he told Reuters.

Buoyed by military gains in Benghazi and by their capture of the oil ports, the LNA has been pushing westwards, promising to retake Tripoli from the armed groups that it says control both the capital and the GNA.

Political figures and military commanders from Misrata have broadly favoured the GNA, whilst Haftar and his allies have refused to support it.

Misrata’s fighters finished a campaign to oust Daesh from their former stronghold in Sirte last month, and commanders from the city – including Baitulmal – had said they would resist with force if Haftar tried to advance into western Libya.