KHARTOUM, Sept. 21 (Xinhua) -- About 100 people were killed during the latest tribal clash in southern Sudan, where witnessed mounting tribal violence this year, sources from the UN peacekeeping forces said Monday.
Thousands of armed men from the Lou Nuer tribe attacked the village of Duk Padiet in Jonglei state Sunday. The fighting killed about 100 people, including about 80 civilians, the sources of the UN Mission in Sudan (UNMIS) said.
Last month, about 185 Lou Nuers were killed during the tribe clash in the same state.
Some 2,000 people have died in tribe violence across the south this year, according to UN figures.
The Comprehensive Peace Agreement, inked in 2005 to end a two-decade war between northern and southern Sudan, stipulates a referendum in the south in 2011 to decide whether an independent state would be set up in the currently semi-autonomous region.
However, the two peace partners, namely the ruling National Conference Party (NCP) and the Sudan People's Liberation Movement (SPLM), have not ironed out their differences on the referendum.
The SPLM accused the NCP of being involved in the tribal violence in southern Sudan, but the NCP denied the claim.
Jonglei state in Sudan. 
The army of southern Sudan says more than 100 people were killed when a local tribe attacked a rival group in the southern state of .

Gunmen from the  tribe attacked a village of the  tribe on Sunday, driving away security forces who were guarding the remote settlement of Duk Padiet.  army spokesman Kuol Diem Kuol said Monday that the dead include 23 attackers, 28 security forces, and more than 50 villagers, with 46 more injured.

"From the attackers 23 bodies were found on the ground. These attackers were found in uniform with arms and organized in a military organisation in platoons with ," Kuol said.

Jonglei state has experienced multiple deadly clashes involving the Lou Nuer, the Dinka Hol, and other tribes this year.

The area has long been the scene of violent cattle raids between the groups. Southern Sudanese officials say northern Sudan's ruling party is organizing the attacks to spark conflict and undermine the 2005  that ended Sudan's civil war, which calls for the semi-autonomous south to vote on full independence in 2011.

The  has repeatedly denied the accusations.