The National Congress Party said that the SPLA has killed at least five of its officials in Raja County, Western Bahr al-Ghazal.
Agnes Lokudu, head of the NCP in Southern Sudan, believes the murders were politically motivated.
The south Sudanese army said the deaths were the result of a crime of passion by one of its soldiers.
According to SPLA spokesman Kuol Deim Kuol, one of their soldiers had caught the NCP’s top official in the village of Tensah committing adultery with his wife.
He added that he soldier shot the couple and six others who tried to stop him.