Libyan city of Sebha
A rebel fighter from the city of Misrata stands guard outside a conference centre in the southern Libyan city of Sabha April 2, 2012 Getty

As a group of girls made their way home from school in Sabha, the remote capital of Libya's southern desert region, on Thursday afternoon (17 November) they became the victims of a mindless but seemingly innocuous prank.

Some young men from the girls' home district of Manshiya decided to hurl a monkey, kept by a local shopkeeper, at the group. It lashed out at girls, hitting two of them and pulling the headscarf from one, scratching her face.

Residents in Sabha say this kind of bullying would be run of the mill, were it not for the fact that the young men –from the Gaddadfa clan – and the girls – from Awlad Suleiman – find themselves on either side of a bitter tribal dispute.

In the past five days 22 people have been killed in fighting sparked by the monkey prank according to statements by the Sabha Medical Centre. Scores have also been wounded in the clashes.

The feud between the Gaddadfa and Awlad Suleiman stretches back to Libya's 2011 revolutionary war and the decades of favouritism shown to the Gaddadfa when their most famous son, Muammar Gaddafi, ruled Tripoli from with an iron first. Now it threatens to engulf Libya's southern Fezzan region in a bitter and protracted war.

"For the past six months everyone has been expecting a war to come in the south, and definitely this could be the start. This war needed to be triggered by something and it was always going to be something ridiculous," an activist in the Sabha, who asked not to be identified, told IBTimes UK.

As the conflict has centred around Manshiya, where the two tribal groups live side by side, the clashes have pit neighbour against neighbour and have been characterised by street fighting.

After initial skirmishes mortars were deployed, striking the residential area the groups call home. As the Sabha resident spoke via telephone he explained the sound of mortar fire could be heard across the city, punctuated with heavy automatic weapon fire.

Libya 17 February Revolution: Country at a crossroads five years after toppling Muammar Gaddafi IBTimes UK

Over the past year-and-a-half clashes have flared between Awlad Suleiman and the Gaddadfa. However, the death toll in Sabha has already surpassed recent battles between the two tribes. Fears the conflict could spread lie in the national alliances both sides have made, leading to fear of a civil war that would cast east against west.

The Awlad Suleiman, the victors in the 2011 revolution, have aligned with the Government of National Accord in Tripoli, a UN-backed government in an alliance with powerful western militas. The Gaddadfa have aligned themselves with Khalifa Hafter, the nominal commander of Libya's armed forces, a military strongman whose commanders now sit as governors imposing order across the east.

"I think it is an excuse for both sides to pick a fight. For the Libyan Army it will be the accusation that Awlad Suleiman have an armed force and are fighting with their enemy. Awlad Suleiman are claiming the Gaddadfa are Isis," the activist said.

Tribal leaders have intervened to seek a solution to the crisis but in less than 24 hours of the summit being called three of the major groupings, the ethnic Tuareg and Tebu and the Werfella, tribe had all withdrawn, causing the talks to collapse.

"Even though it started with the monkey incident – whatever you want to call it – this has been going on for a long time," the activist said.