By Betel Miarom N'DJAMENA, Dec 12 (Reuters) - Chad's army pursued rebels across the border into the Sudanese region of Darfur on Tuesday, capping several days of clashes in the east of the landlocked central African oil producer, military sources said. The fighting took place three days after a major battle between government forces and rebels from the Union of Forces for Democracy and Development (UFDD) on Saturday, some 50 km (31 miles) north of the eastern regional capital Biltine. Chadian President Idriss Deby flew to Biltine on Sunday to direct army operations in the region, the sources said. Government troops again engaged rebels some 40 km from Biltine on Sunday, but no casualty figures were immediately available. Tuesday's clashes took place at Hadjar Marfaine, some 750 km (470 miles) from the capital N'Djamena and close to the Sudanese border. Casualty figures were not immediately available. "The forces of defence and security entered 20 kilometres inside Sudanese territory," said a regional military commander, who asked not to be identified. "The clean up operation continues." Chad accuses the Sudanese government of supporting the insurgents. It says rebels and Arab militia raiders in Sudan's western Darfur region are spreading across the region, destabilising central Africa. Khartoum denies this. The rebels, led by Chad's former defence minister Mahamat Nouri, have threatened to launch a fresh attack on the largest city in the east, Abeche, which they briefly captured last month before retreating to the desert. "Abeche is calm," said the military commander. "We are waiting for (the rebels) with feet firmly planted." Over the last year, several rebel groups dedicated to toppling Deby have fought a low-intensity war in the desert, mountains and scrubland of eastern Chad, occasionally striking further west. In April, the rebels reached N'Djamena but were repulsed after hundreds of people were killed in fighting. Former fighter pilot Deby, in power since 1990, won a new five-year term at elections boycotted by the opposition just weeks later.
