More than 3,000 South Sudanese have fled into the neighbouring Uganda on Tuesday after fresh began on border town of Pajok.
In the morning raids, that involved government soldiers, undisclosed number of men, women and children were killed indiscriminately.
These are latest raids to hit southern towns near Ugandan borders as three-year civil war spreads across the world’s youngest country.
According to a report by Ugandan intelligence officials and fleeing refugees, the fighting started at 8.00 am on Monday with a three pronged raids on Pajok town that is home to more than 50,000 people.
Crisis erupted in South Sudan late March after rebels loyal to former vice president Riek Machar said they freed prisoners from a jail in another border town of Kajo-Keji about 100 kilometers (60 miles) south of the capital Juba.