Over the last few days, Chadian troops have pursued Chad rebels into Sudan, in an attempt to eliminate the rebel bases. The Chad forces are avoiding contact with the Sudanese army, but the pro-government Sudanese militia groups appear to be coming to the aid of the Chad rebels. So there may be some fighting inside Chad between the Chadian army, and the Chad rebels/Sudanese militia. Someone has been spending big money on the Chad rebels, as they rolled into Chad recently in expensive pick-up trucks, and heavily armed.
The government claims to have inflicted a major defeat on the SCUD rebels, killing 700 of them, as well as some of the leaders. There have been pictures of dozens of burned out rebel trucks in areas along the Sudanese border. The Chadian rebels are a mixed lot. Mainly, they are former allies of president Deby, who is more concerned with holding on to the new-found oil revenue these days. Deby's former friends disagree with how Deby is dealing with the growing violence on the Sudan border, although much of the rebel activity is caused by tribal politics. Other rebel groups are an extension of the Afro-Arab/black African conflict. Both groups exist in Chad, some of them part of tribes that straddle the border. Tribal politics is a big thing in Chad, as it is in most of Africa.
Aid groups are pulling out of the area, and trying to move thousands of refugees, in order to avoid the violence in eastern Chad. Most of the groups from Sudan operate like bandits, stealing whatever they can to get by. Aid groups have a lot to steal. The aid workers don't have much protection from this, because locally hired security guards are no match for large groups of bandits/rebels/militia.