Khartoum (AFP) - A staffer from the International Organisation for Migration has been abducted in Sudan's Darfur, the IOM said on Monday.
It is the latest incident of its kind in the region where crime and other violence has surged.
"An IOM colleague has been abducted from South Darfur at about 5:30-6:00 pm Sunday," Maysaa Alghribawy, acting officer in charge of IOM's Sudan mission, told AFP.
She could provide no further details.
The kidnapping follows the disappearance last month of two Sudanese employees of the Irish aid group GOAL. They were taken while travelling on assignment near Kutum town in North Darfur.
Also in June, an Indian contractor with Darfur's UNAMID peacekeeping mission was freed after 94 days in captivity. He was abducted by armed men in El Fasher, the North Darfur capital.
In another recent case, a UNAMID peacekeeper spent almost two months in the captivity of an unidentified group until his release in South Darfur in May.
Insurgents from black tribes in Darfur rose up 11 years ago against what they said was the domination of Sudan's power and wealth by Arab elites.
In response, the government turned to "Janjaweed" militia recruited from Arab tribes, and who have since been incorporated into official paramilitary units.
Officials acknowledge "they are increasingly losing control over paramilitaries, who have been the main source of insecurity in Darfur for two years", the International Crisis Group of analysts said in a January report.
Militias in search of resources have turned on each other, and sometimes against the government, while violent crime has increased.
Carjackings and robberies drove a doubling of security incidents involving foreign aid groups in Darfur last year, UN data obtained by AFP in February showed.