Aid agencies are calling on the international community to take urgent action to help the growing number of Sudanese refugees in eastern Chad. More than a million mainly black Africans in Sudan's western Darfur region have been driven from their homes by gangs of Arab militia. Around 180,000 have sought sanctuary in neighbouring Chad. A representative of the UN refugee agency says the response to recent aid appeals has been disappointing. The approaching rainy season will also soon make it hard to reach those in need.