Mani Arkoi Minawi, secretary general of the movement, told journalists in Cairo that: "SLM forces have seized control of the garrison of Al-Teinah and killed about 250 government soldiers after fierce fighting,".
Fourteen military vehicles were captured, he said, while the SLM's losses were only one dead and seven wounded. The fighting happened in the Darfur region of western Sudan
The governor of north Darfur State, Osman Yusuf Kubur, told journalists about 200 rebels launched the assault on Al-Teinah on Monday.
But he said government forces chased SLM troops out of town and destroyed a number of their vehicles.
Some crossed the border and engaged in fighting with Chadian army troops, Kubur added.
Last Saturday, the governor said 15 Sudanese soldiers and 30 rebels were killed when Darfur separatists attacked the border garrison town.
The SLM since late February 2003 has carried out several attacks on government forces in the remote and partly desert region of Darfur, which lies on the border with Chad.
Founded March 2003
Seeks a devolved, federal Sudan
Chief spokesman, Mani Minawi, based in Cairo
Denouncing policies of alleged “marginalisation, racial discrimination, exclusion, exploitation and divisiveness”, the SLM and its military wing, the Sudan Liberation Army, announced their formation in March 2003.
Its objective is complete restructuring and devolution of power for all regions of the largest African country.
Minawai said in March the “SLM shall struggle to achieve a decentralized form of governance based on the right of Sudan’s different regions to govern themselves autonomously through a federal or confederal system.”