When Sudan split into two independent states in July, it was a fragile moment for both countries, but far more so for the south. Euphoria was quickly followed by warnings that lingering tensions, and institutional weaknesses, would make celebrations short-lived.
Now comes word that more than 3,000 people, mostly women and children, have been killed in South Sudan in a dispute over cattle rustling. Just as the observers warned, violence and tribal fighting threatens to destabilise the world's newest nation.
Some 6,000 Lou Nuer youths, armed with AK-47s, began attacking the Murle people's stronghold of Pibor last week . The government says it has full control over Pibor and warned that ethnic violence could lead to a "major tragedy". The presence of forces is certainly important to prevent more bloodshed in the area, but it is not enough.
Like many challenges facing South Sudan, these conflicts are as deeply rooted as they are historic. The practice of cattle raiding, known in Sudan as hambata, is centuries old and is often associated with lack of security during conflict or war. It is a tradition often carried out to demonstrate a man's maturity or a tribe's power, not necessarily for survival needs.
The persistence of tribal violence has been largely a result of state negligence. The former government in Khartoum bares a share of the blame; for decades, the nomadic tribes were politically and economically isolated.
Now this is Juba's problem. As it embarks on building the new country and its institutions, tribes must be involved in this process. Development projects should provide the tribes with a sense of security and grant them access to health and education.
There are more than humanitarian reasons to demand an end to this slaughter. Continued tribal violence might have economic implications, such as the disruption of oil pipelines, and tribal violence could easily spill over the borders, where rival tribes live.
Tribal violence is a complex issue facing the fledging country of South Sudan. Security is an immediate need, but over time, reconciliation between warring tribes will be vital. For a young nation, this will be a tall order. But it is an order Juba must deliver on.
