Planes reportedly belonging to the Libyan air force carried out air strikes on positions in Tripoli on Monday as the militia war that has gripped nation’s capital continued to escalate.

Though witnesses identified the planes as Libyan army aircraft it is not known who ordered the attack.

Many units of the official Libyan army and air force have pledged loyalty to the retired Major General Khalifa Haftar, who is currently waging a war against the country’s Islamist militias without the backing of the central government.

The airstrikes follow two days of heavy shelling in the capital as rival militias fought to seize control of territory.

In a statement released on 17 August the United Nations Support Mission to Libya (UNSMIL) condemned the escalation in violence and denounced the shelling of civilian neighbourhoods.

“UNSMIL deeply regrets that there was no response to the repeated international appeals and its own efforts for an immediate ceasefire,” is said in a statement.

“The Mission warns that the continued fighting poses a serious threat to Libya’s political process, and to the security and stability of the country.”

Dozens have been killed and thousands have been displaced in the latest round of militia warfare that started in the capital on 13 July.