Mohamed al-Beel Issa Zayyed, deputy head of the Justice and Equality Movement (JEM), announced that government forces and the rebel movement clashed in South Kordofan, on Monday 15 October.
Zayyed, who is also secretary of South Kordofan, told Radio Dabanga that dozens of government forces were killed, including the force commander.
He added that the rebels destroyed three army vehicles and seized two another two that were carrying large quantities ammunition and weapons.
The deputy head of JEM explained that his troops clashed with government forces at approximately two o'clock on Monday afternoon in the area of Umm Zeifah, located between a petroleum field and Yama in Mujlad locality.
Radio Dabanga was not able to reach the Sudanese army for comments.