The East African organization that has been trying for months to broker peace in South Sudan, on Friday condemned the latest violation of a seven-month-old cessation of hostilities deal after fighting raged for hours in Bentiu.
The Intergovernmental Authority on Development (IGAD) condemned "in the strongest terms the continued flagrant violation of the Cessation of Hostilities agreement that was signed on 23 January 2014 by the Government of the Republic of South Sudan and SPLM/A - In Opposition."
IGAD said in a statement that it was "particularly dismayed by the latest fighting that happened just days away from the IGAD Assembly of Heads of State and Government summit meeting and less than 48 hours after the departure of the U.N. Security Council team that visited the region."
IGAD repeated a message to the warring sides in South Sudan "that military advances to gain more ground by will not achieve anything except to worsen the already catastrophic humanitarian situation and to cause further devastation."
IGAD was notified of the fighting in Bentiu by a Monitoring and Verification team that is deployed in Unity state. Monitoring and Verification teams were a key provision of the January 23 peace deal, but have been slow in getting off the ground.
Clashes in Jonglei state
Lt. Col. Joseph Marier Samuel, a spokesman for the army, confirmed that there had been clashes in Bentiu and said rebel forces also attacked SPLA positions in Ayod, in Jonglei state, early on Friday.
"In this attack, the rebels have been repulsed leaving behind 120 dead on the ground," Marier said. "On our side we lost six soldiers and 11 wounded."
Marier called the clashes "a continuous violation of the ceasefire agreement" by the opposition. He insisted the SPLA has always respected the January 23 Cessation of Hostilities agreement and only engaged in combat in self-defense.
Opposition says SPLA attacked first
The opposition had an entirely different version of events, saying its forces had been attacked by government troops.
"Government forces launched fresh attacks on our positions east and south of Bentiu and we engaged them in a three-hour battle," opposition military spokesman Lul Ruai Koang told South Sudan in Focus.
Koang said the fighting started in Thou Mangue and spread to the Unity state capital, Bentiu, as "government forces retreated under heavy artillery fired from our forces."
He said the fighting had ended by the afternoon and the opposition was "doing mop-up operations."
Koang refused to comment on the death toll in the fighting.
More civilians seek UN protection
The U.N. Mission in South Sudan (UNMISS) said in a statement that some 400 civilians fled the fighting in Bentiu and sought shelter with UNMISS troops stationed at the airport. UNMISS escorted the civilians to the UNMISS compound outside Bentiu once the fighting had died down.
The United Nations' humanitarian coordinator in South Sudan, Toby Lanzer, praised the "swift action" taken by UNMISS "to protect the people who sought shelter at the airport."
Nearly 100,000 civilians have sought shelter at U.N. compounds around South Sudan since fighting first erupted in Juba in December, before spreading to other parts of the country.
Bentiu has been the site of fierce fighting during the eight-month-old conflict, on which the January 23 peace deal had little impact.
In April, UNMISS accused opposition forces of carrying out targeted killings, including of children, and inciting "vengeful sexual violence" against women after they once again captured Bentiu from government troops.
Lucy Poni contributed to this report from Nairobi.