A Germany aid agency said on Friday it has evacuated eight of its workers out of the southern Sudan and brought them to capital Khartoum as a temporary measure as tribal fighting flares up in the vast region.
In a statement issued in Nairobi, Deutsche Welthungerhilfe ( German Agro Action) said its staff member and seven Sudanese are now in safety, while twelve others have not yet been able to leave.
"The clashes began as a local dispute on Monday. They then escalated and spread," said Johan van der Kamp, Welthungerhilfe's regional coordinator in Sudan.
"As many as 28 deaths have since been recorded, 17 are civilians," van der Kamp added.
For the first time since the landmark peace agreement was signed in Nairobi last year, fierce fighting has flared up again between the Sudanese army and the former rebel movement SPLA ( Sudan People's Liberation Army) and their militias in Rubkona in Unity State province.
"There are at least five uneasy years to go before the referendum," explains van der Kamp.
"In the areas under dispute a buffer zone needs to be created between the armies, and the military should leave the civilian areas," he said.
He said the army still constantly presented in the streets of towns like Rubkona, so lots of civilians are at risk whenever violence flares up.
Van der Kamp said it was "sad" that the UN Mission in Sudan ( UNMIS) was unable to prevent these incidents from getting out of control.
Deutsche Welthungerhilfe has been active in Sudan since 1998, working in the provinces of North-Darfur, West Kordofan and Unity State and project priorities include agriculture, food security and drinking-water supply.