The Sudanese authorities in the disputed area of Abyei say at least 32 people have been killed after gunmen stormed local villages.
The Information Minister for Abyei, Bolis Kuoch, said more than 20 others were wounded when men opened fire on Sunday morning.
He said UN peacekeepers intervened to stop the violence but one of the peacekeepers was killed.
There have been ongoing hostilities between communities in Abyei over land and resources.
The region, rich in oil reserves, lies on the border between Sudan and South Sudan and is considered to be part of both countries, since a peace agreement was signed in 2005.
Last week the UN Security Council extended the mandate of its peacekeeping mission there for one more year.