Unknown gunmen killed a Sudanese employee of the U.N. World Food Programme (WFP) in the southern border state of South Kordofan where the army is fighting an insurgency, the WFP said on Sunday.
Two gunmen opened fire on a U.N. car 80 km (50 miles) north of the state capital Kadugli and killed the driver, a WFP spokeswoman said.
A second person in the car was injured, she said, adding details of Saturday's incident were still unclear.
The Sudanese army has been fighting for more than a year rebels of the SPLM-North in South Kordofan, which borders South Sudan. Fighting spread to the Blue Nile border state in September.
Sudan accuses South Sudan of supporting the rebels, a claim some diplomats find credible despite