What is Chad worried about?

The presidents of Sudan and Chad have met to discuss the humanitarian crisis in Sudan’s troubled western region of Darfur. Presidents Omar al-Bashir of Sudan and Idriss Deby of Chad held talks in west Darfur’s capital. There were no immediate details about their meeting. But officials said the leaders have been expected to discuss setting up a patrol along the shared border to stop Arab militias in Darfur from crossing into Chad to carry out attacks. The government-allied Arab militias have forced more than 1,000,000 black Sudanese from their homes in Darfur. An estimated 130,000 of them have fled to neighboring Chad.