South Sudan is rejoicing over the peaceful conduct of its long-awaited vote for independence and the international community is lauding the process. President Obama called the referendum on whether the semiautonomous region will secede from Sudan "an inspiration to the world."

But a hotly contested zone in the heart of Sudan is once again threatening to explode – an event that could derail all efforts toward a peaceful divorce in Africa’s largest country.

The tug of war between the north and south over the future of the oil-rich border town of Abyei has heated up in the past week. A series of clashes between the two tribes who stake claim to the territory illustrate how the future of this region – and of Sudan – remain up for grabs.

Here on the north-south faultline, northern Arab herdsmen – whose large herds need Abyei’s fertile pasturelands and the river that cuts through the territory – have long been at odds with the Ngok Dinka people, mostly non-Arab farmers who claim that international court rulings and peace deals meant to protect their ancestral rights to this land have been repeatedly dishonored.

While southerners have turned out en masse since Sunday to decide the future of their oil-rich but underdeveloped, Texas-sized territory, the residents of Abyei have been denied that right, partly because the ruling parties in the north and south could not agree on the definition of an Abyei resident, and therefore who should be eligible to vote in the Abyei referendum.

Although conventional wisdom on Abyei says that the region’s oil deposits are the reason why neither Khartoum or Juba are willing to cede ground on Abyei, experts say the issue is more about the challenges of Sudan’s diverse populations living together and sharing land that both believe is rightfully theirs based on their community’s histories and lore.

Some Misseriya and Ngok Dinka leaders say they think the other group is being manipulated by higher political interests in the north and south. At a conference this week in the capital of the northern state of South Kordofan, which borders Abyei and is home to much of the Misseriya population that migrates south into the area, tribal leaders pledged to band together to appeal to the Sudanese presidency – which includes president Omar al-Bashir and the southern leader Salva Kiir – to find a solution for Abyei.

Recent clashes

Accounts of the attacks which occurred around 10 miles northwest of Abyei vary widely, but according to a number of Ngok Dinka sources in Abyei and to various southern officials, about a half dozen police were killed while defending an outpost attacked by armed Misseriya and assorted Khartoum-backed militia fighters just north of a village of Ngok Dinka. For their part, Misseriya elders claim the police fired on them, and that herders were merely defending themselves.

In any case, proxy militia or military involvement seems very likely. Ngok Dinka claim the Misseriya who attacked the police post of Maker Adhan were armed and reinforced by northern security forces, including the oil police that guard fields that were formerly part of Abyei, until the 2009 Hague ruling altered the existing but disputed boundaries. Some Misseriya accuse the joint north-south police force providing security in Abyei of being dominated by southern army soldiers disguised as police.

'Joint integrated units'

The town of Abyei is humming with armed men in several different uniforms. The “joint integrated units,” from the northern and southern armies, also socialize in the market, with the northern officers drinking tea in one stand and southern officers mingling with their friends in another area.

Meanwhile, blue camouflage signals the presence of the Abyei police, who are also meant to be a joint north-south force, but who seem dominated by commando-style young officers in pick-ups armed with heavy machine guns not typically used by the police, even in Southern Sudan.

As one observer who couldn’t be named due to his position in the Abyei government noted, these police officers are “trained as soldiers.”

The joint north-south police force was created in the aftermath of the 2008 violence, and although the joint military units do limited patrolling in Abyei, the police remain the main security force for the territory.

No longer safe

Today, as the future of the region remains to be determined, Abyei is not a safe place for any of its residents or would-be returnees, thousands of whom are camped in Khartoum waiting to move home until security improves.

James Nyoi, 28, arrived in Abyei a week ago on a bus convoy full of Abyei residents returning home after years spent living in the north. He says armed Misseriya and some men wearing northern army uniforms dragged him off a bus as the convoy attempted to pass near the near the oil installation of Diffra, which the 2009 Hague ruling placed outside the boundaries of Abyei.

They took the $450 he had in his pocket – all of his savings – and his cellphone and beat him over the head with sticks. Eventually the convoy was allowed to pass, with Mr. Nyoi and other traumatized passengers back on board. “These are bad people,” says Nyoi. “You cannot describe them as part of humanity.”

Bus drivers in Abyei say they’re afraid to ply their usual route to Khartoum.

“In this kind of situation where we are living, I don’t think I’ll be going [back to Khartoum],” says Biong Kuol, who drives a bus boasting the phrase “military experience” along with iconic photographs of the late southern war hero John Garang and the current southern president Salva Kiir.

If violence resumes on a larger scale, which could take the form of Misseriya and allied militias pushing through police stations like the one they were repulsed from last weekend, it is not clear how the violence could be contained and by whom.

With local trust of authorities like the Abyei government and the UN peacekeepers stationed in the town at a low, anticipation that the people of Abyei will be abandoned as they were in 2008, when Sudan’s northern and southern militaries clashed and 60,000 people fled south.

“They are ready to run,” says David Deng, an American who lives in Abyei and is the son of a well-known politician from the area. “That’s their plan and they know how to protect the women and children,” he said, noting that many had done this in 2008.

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