The extent of the clashes, which erupted one day earlier when fighters from the Lou Nuer tribe raided a rival village, emerged on Monday after officials reached the remote settlement.
Kuol Diem Kuol, a spokesman for the South's Sudan People's Liberation Army (SPLA), said a total of 51 villagers and 28 soldiers, police and national security officers had been killed.
"From the attackers, 23 bodies were found on the ground. These attackers were found in uniform with arms and organised in a military organisation in platoons with G3 rifles," Kuol said.
Mayen Ngor, the commissioner of Duk County, said the attackers had burned down 260 huts, the police station and local government buildings.
"This is a campaign against the Comprehensive Peace Agreement [the 2005 accord that ended Sudan's north-south civil war] and against the people of Duk," he said.
The attack injured 46 people and forced thousands to flee, according to Ngor.David Gressly, a regional co-ordinator in south Sudan for the United Nations Missions in Sudan, said the attack appeared to have targeted SPLA forces based in the village.
"It is quite clear that the focus of the attack was on the organised forces themselves," he said.
"It is way too early to call this a civil war, but it is a significant law and order problem and one that the government of southern Sudan needs to stand up and address," he told the AFP news agency after visiting the area.
A surge of tribal killings this year has sparked fears for the stability of Sudan's under-developed south.
The United Nations estimates more than 1,200 people have died in ethnic attacks this year.
The Sudanese People's Liberation Movement (SPLM), which heads an autonomous regional government in the south, fought a two decades long civil war with the northern National Congress Party (NCP), now headed by Omar al-Bashir, Sudan's president.
The two parties signed a peace treaty in 2005, but tensions have remained.
Source: Al Jazeera (English)