(CNN) -- Fifty-seven "militiamen," including several high-ranking officers loyal to militia leader Gabriel Tang, were killed when Tang's forces attacked the Sudan People's Liberation Army in Southern Sudan, officials said Sunday.
Tang's forces launched the attack at Kaldak on Saturday, the Sudan People's Liberation Army (SPLA) said in a statement issued on behalf of Gen. Malaak Ayuen of the South Sudan Army. The SPLA is the military wing of the movement that governs Southern Sudan.
The SPLA killed 57 of Tang's forces, including three major generals and a number of brigadier generals, according to the statement. In addition, one major general and other brigadier generals were captured, the statement said.
Tang himself "narrowly escaped" the fighting, according to the statement.
Officials said it was unclear why Tang's forces attacked the troops, but the SPLA said it believes he has been in contact with other rebel groups in the region.
CNN's Nima Elbagir contributed to this report.