At least two thousand people last week fled their homes in Blue Nile to South Sudan.
The refugees walked for eight days from Baldogo village 34 kilometres south of Bau town, Bau locality to the Albonj area, UN Office for Coordination of Humanitarian Affairs or OCHA reported.
The office said the people fled their homes out of fear over the possibility of attacks by the Sudan Armed Forces or SAF in the area.
OCHA said this information was not verified independently as there are no humanitarian organisations operating in the area.
UN Refugee Agency or UNHCR said some 231 thousand Sudanese refugees from South Kordofan and Blue Nile sought shelter in South Sudan and Ethiopia since June 2011.