Political leaders from Sudan's north and south and a top U.N. official met in the embattled border zone of Abyei on Friday in an attempt to broker peace after a wave of attacks killed more than 100 people.

Fighting broke out in Abyei last Sunday, and southern political leaders blamed the attacks on the north's military. The northern government maintains the southern government is responsible for the clashes due to its failure to remove pro-southern police from the contested area in line with a January agreement.

Abyei is a fertile region that has oil deposits in between north and south Sudan. Southern Sudan voted to secede in January and is slated to become the world's newest nation in July.

Abyei's future is very much up in the air, and observers worry the region could re-ignite a new war between the north and south.

"The U.N. initiated the idea that this meeting should be held as a matter of urgency," Hua Jiang, spokeswoman for the U.N. mission, told The Associated Press by phone on Friday from Abyei.

"The purpose of this meeting is to try to stop the current violence and also allow the migration to take place, to proceed," she added, referring to the yearly migration of the Arab cattle-herding Misseriya people, whose seasonal grazing through the fertile Abyei region has been delayed this year due to insecurity in Abyei.

The U.N. delegation was led by Haile Menkerios, head of the billion-dollar-per-year U.N. peacekeeping mission in Sudan. It also included the acting force commander of the U.N.'s 10,000 troops.

The governor of Southern Kordofan state, Ahmed Haroun, also attended. Haroun, who is allied with the Khartoum-based north, is wanted by the International Criminal Court in The Hague on charges of war crimes for his role in the ongoing conflict in the western region of Darfur.

Another official from Khartoum's ruling National Congress Party in attendance is Salah Gosh, the former director of Sudan's National Security and Intelligence Services who currently serves as President Omar al-Bashir's adviser for national security. That could anger the Ngok Dinka, a southern tribe that believes Gosh is organizing the violence.

The south was led by the Minister of Regional Cooperation Deng Alor. Alor is a Ngok Dinka native of Abyei.

The top official in Abyei, Deng Arop Kuol, told the AP on Thursday that the northern military, known as the Sudanese Armed Forces, had participated in the Wednesday attack that killed scores of police who attempted to defend a police post in Maker Abyior when it came under attack from Misseriya militia forces.

These claims have not been independently verified, and Kuol said Friday that insecurity is preventing U.N. peacekeepers in Abyei from visiting the sites of the attacks.

An internal security report by the U.N. and seen by the AP estimated that "about 20,000 to 25,000 people" — about half the population of Abyei — may have left.

The U.N. mission announced Wednesday that it was deploying an additional company of peacekeepers to Abyei. Jiang said the company would include between 100 and 130 troops.

Following violence in early January in Abyei that killed more than 60 people, the United Nations helped broker an agreement between the northern and southern governments to bolster security. The agreement was intended to allow the Misseriya to migrate with their cattle and to enable the safe passage of tens of thousands of southerners streaming home from northern Sudan in advance of the south's independence in July.

This agreement has not been implemented, and insecurity has reigned in the past months in Abyei.

Abyei had been promised its own self-determination vote in the 2005 north-south peace deal that ended decades of civil war, but disputes between the political leaders from north and south prevented the Abyei referendum from happening.