Bowing to international pressure, the government has opened routes for relief aid to western Sudan. The fighting is still going on, but it is mainly groups of raiders looting and clearing civilians out of villages and driving them into Chad. While the raiders and victims are both Moslem, the west Sudan tribes.
The heart of the resistance in western Sudan is the Sudan Liberation Army' (SLA) and the Justice and Equality Movement (JEM). The two groups are quite different, and all they have in common is hostility towards the current government. SLA is largely tribal, and represents many disagreements some of the 80 tribes in western Sudan have had with the government. Most SLA members are from the Zaghawa tribe, whose territory is found in Chad and Sudan. The president of Chad is a member of the Zaghawa tribe. Eritrea, which has disputes with Sudan in the east, has provided aid to the SLA. The tribal violence is basically over control of water and land, both of which have become relatively scarce as population increases. The greater availability of post Cold War weapons (mainly AK-47s) has made raiding and banditry deadlier. Bandits have always been a problem, but now armed with AK-47s, they are deadlier.
JEM is composed of Islamic militants who disagree with the Islamic conservatives who are running the government. JEM is getting outside money as well, probably from charities supported by conservative Persian Gulf donors.