Group: Residents of Abyei flee from advancing Sudanese troops

(CNN) -- Advancing Sudanese troops have prompted a massive evacuation by inhabitants of the oil-rich city of Abyei, a humanitarian medical group said Monday.

The organization, Doctors Without Borders, said many of the evacuees have fled 40 kilometers (24 miles) south to Agok. That includes 42 people wounded in violent clashes over the weekend who are being treated at the aid group's hospital there.

"This morning, the entire population of Abyei town fled the city, which is now almost empty," the organization said in a statement.

Meanwhile, a spokesman for the military wing of the movement that governs Southern Sudan confirmed Sunday that Sudan's military had taken control of the oil-rich region.

"Abyei has been under attack by the Sudanese armed forces from air and ground," said Sudan People's Liberation Army (SPLA) spokesman Philip Aguer.

Southern Sudan in January voted to split from the north, and is expected to officially become an independent nation in July.

However, the fate of the oil-rich Abyei region remains a flash point.

The Sudanese armed forces said the military in Southern Sudan was behind the attack, but the SPLA denied responsibility.

A statement from U.N. Secretary-General Ban Ki-moon's press office noted that the U.N. compound was shelled by mortar rounds, leaving two peacekeepers injured.

The release, from Ban, also asked for "justice" following earlier attacks May 19 on a U.N.-escorted convoy and on U.N. troops May 10 in Goli. At least 22 people were killed in the more recent attack, which was on Sudanese armed forces and U.N. peacekeepers, according to Sudanese army sources.

"The Secretary-General remains deeply concerned for the safety of the civilian population of the area, the vast majority of whom (have) been forcibly displaced due to the fighting," the U.N. statement said Sunday. "The Secretary-General calls on both parties to immediately cease their military operations, withdraw all forces and armed elements from Abyei and desist from further acts of antagonism."

The Commission of the African Union responded to the latest developments in Abyei "with very grave concern," according to a prepared statement released Sunday.

"The AU Commission would like to urge all the parties to immediately withdraw all the unauthorized forces from the area ... and to restrain from any provocative actions," the statement read. "The AU Commission calls on the parties to resume the dialogue towards a political settlement on Abyei by returning to the negotiating table."

Sudanese President Omar al-Bashir issued a decree Saturday dissolving Abyei's administration. The area had been governed by representatives from the north and south.

The United Nations said this month that violence in the Abyei region will jeopardize relations between the two sides as they gear up for a permanent separation July 9.

Its peacekeeping mission in Sudan issued a statement Saturday urging "all parties in Abyei to resume dialogue towards reaching a lasting political settlement."

British Foreign Secretary William Hague condemned the recent spike in violence.

"I call on all sides to cease hostilities immediately. All unauthorized forces should be withdrawn from the entire area of Abyei in accordance with past agreements by the parties," he said in a statement Sunday.

In a statement Saturday, the White House called on the Sudanese Armed Forces to stop its offensive in Abyei and withdraw forces.

"Failure to do so could set back the process of normalizing relations between Sudan and the United States and inhibit the international community's ability to move forward on issues critical to Sudan's future," the statement said.

A U.N. Security Council delegation had arrived in Khartoum, Sudan, on Saturday to discuss the ongoing peace process with government officials.