A ceasefire in  Ain el- Helweh, Lebanon’s largest refugee camp, was broken late on Thursday evening by fresh clashes between Fatah – the camp’s dominant faction – and armed Al Qaeda-affiliated groups.

While sounds of automatic weapon fire and rocket launchers were heard, there were no immediate reports of casualties.

Lebanon’s state media agency said “a large number” of  Ain el- Helweh residents fled their homes, heading towards a mosque.

Videos circulating on social media showed dozens of residents escaping the vicinity of the fighting on foot and in cars.

In another video, dozens of rocket-propelled grenades streaked from one end of the camp to the other as the sounds of machinegun fire echoed.

The Palestinian Joint Action Committee in Lebanon, comprising representatives of Palestinian political factions, called "a ceasefire in  Ain el- Helweh camp to allow the joint Palestinian security force in the camp and the Joint Action Committee in Saida to carry out their duties".

There had been a tentative calm throughout the camp for weeks after days of deadly clashes between Fatah and other factions in late July and early August killed at least 13 people and injured dozens more.

The battle for control of the camp broke out after the assassination of high-profile Fatah security forces commander Abu Ashraf Al Armoushi.

Fatah had previously given the Islamist insurgents – among them the Al Qaeda-affiliated Jund Al Sham group – a deadline to surrender the killers of Al Armoushi, or face deadly retribution.

The deadline passed last week.

Al Armoushi’s killers were not handed over.

Since the fighting ended, the Islamist insurgents have been fortifying their positions inside two UN schools in the camp.