The Intergovernmental Authority on Development (IGAD) said Monday that one of its ceasefire monitors has died in Bentiu after being detained by opposition forces.
IGAD, which is leading peace talks for South Sudan, did not name the man but said he was part of a verification team that was in Unity state on Saturday on a routine inspection mission.
Shortly after arriving in Bentiu, the monitors were "arrested and marched to an unknown destination," IGAD said. The man died of natural causes, IGAD said.
The U.N. Mission in South Sudan (UNMISS) said the man who died was a liaison officer for the Sudan People's Liberation Army (SPLA). UNMISS said he was part of a team of six ceasefire monitors and three air crew and confirmed he died of natural causes.
The other IGAD monitors and the air crew were rescued and flown to the UNMISS base in Bentiu on Sunday, UNMISS said.
South Sudan in Focus was unable to reach SPLA spokesman Philip Aguer for comment.
Ethiopia's former foreign minister, Seyoum Mesin, who heads IGAD's South Sudan mediation team, told reporters in Addis Ababa at an extraordinary summit for South Sudan that those responsible for the ceasefire monitor's death will "bear the consequences."
In a statement released after the heads of state meeting on South Sudan, IGAD deplored the repeated violations by both government and opposition forces of a January ceasefire agreement, under which the monitoring teams were set up.
Fighting continued after the signing of the January 23 cessation of hostilities agreement and the monitoring teams were only deployed months afterwards, amid concerns for their safety.
In the statement, IGAD also condemned the failure of the warring sides to set up a transitional government by the August 10th deadline that they agreed to, and warned that, with fighting still continuing, South Sudan is slipping closer to a famine that would be devastating for the country and the entire region.