Juba — South Sudan army (SPLA) forces on Thursday repulsed a militia attack, in which seven rebels were killed in the Obudi area of its Upper Nile state, a military source said.
"The army was able to repulse an attack carried out by the militias in our territory. The SPLA will continue to protect the people of South Sudan from such aggression", SPLA spokesperson Phillip Aguer told a media briefing in Juba, on Friday.
He accused the Sudanese government of backing the militias.
The incident comes barely a week after the SPLA said one of its soldiers died in a ground and air attack allegedly carried out by the armed forces from neighbouring Sudan in the Renk county of Upper Nile.
At least three people, the army said, were wounded during the attack, which has reportedly displaced thousands of women, children and the elderly in the state.
South Sudan seceded from Sudan in 2011, but tensions between the two nations almost triggered a border conflict in April last year. A 2005 peace deal allowed South Sudan to opt for independence, but many other aspects of the deal, such the status of disputed areas and demarcation of the border have not yet been fully implemented,
The two sides signed a deal in September last year that would have allowed South Sudan to resume oil exports - stopped a year ago over a transit fee dispute - and create a demilitarised buffer zone on the tense border.
However, implementation of the deal has stalled over security issues, with Sudan accusing the South of backing its former comrades who fight the Sudanese army in South Kordofan and Blue Nile - both of which border Upper Nile state.
Khartoum and Juba deny accusations of supporting rebel groups from both sides.