N'DJAMENA, Dec 8 (Reuters) - Chad's army has retaken the eastern town of Biltine after launching a counter-attack against rebels who briefly occupied it in their military campaign against President Idriss Deby, the government said on Friday. "Our defence and security forces are pursuing the rebels," Defense Minister Bichara Issa Djadallah told reporters. The rebel Union of Forces for Democracy and Development (UFDD) said on Thursday its fighters had moved into the town, the capital of the eastern Biltine prefecture, without encountering any serious resistance from government troops. UFDD spokesman Ali Moussa Izzo told Reuters by satellite phone on Friday the rebels had pulled out of the town but were controlling the area around it. "To avoid a battle in the town we withdrew," Izzo said. Djadallah said government forces had killed 50 rebels and captured 30. He put government losses at 10 dead and said 10 rebel vehicles were destroyed and 10 captured. There was no independent confirmation of the casualties. Biltine borders with Sudan's conflict-torn western region of Darfur, where tens of thousands of people have been killed in political and ethnic conflict since 2003. Over the last year, several rebel groups have fought a low-intensity war against Deby's forces in the desert, mountains and scrubland of east Chad, occasionally striking further west. In April, rebels raided the capital N'Djamena, some 700 km (450 miles) west of Biltine, but were repulsed. In the last two weeks, rebels briefly occupied the main eastern city of Abeche and several other eastern towns, including Biltine, pulling back when government forces moved against them in strength. Deby says the conflict in Darfur is pouring rebels, Arab militia raiders and refugees into Chad and accuses Sudan of backing marauding armed groups trying to destabilise his rule. Khartoum denies this. Chad's government on Friday appealed to the international community to contribute to a fund it was creating to provide aid to an estimated 150,000 civilians displaced by recent attacks and inter-community violence in the east. As a result of the fighting, U.N. agencies and some aid NGOs have been pulling back staff from some towns in eastern Chad, where more than 200,000 Sudanese refugees from Darfur live in 12 camps in the border region.