N'DJAMENA (Reuters) - Chad said its air force had completed raids on "mercenaries" inside Sudan on Sunday, announcing its aircraft had destroyed seven groups of fighters while ground forces had captured 100 prisoners on the border.
Tensions between the two oil-producing neighbours escalated over the weekend after Sudan complained Chad had launched a series of bombing raids on its territory on Friday, calling the move an "act of war."
Chad had not previously confirmed the raids but said it was justified in sending its armed forces into Sudan due to the support the government in Khartoum allegedly provided ahead of and after a failed attack by rebels on Chad's army last week.
"Our defence and security forces have completely withdrawn from Sudan this afternoon," said Adoum Younousmi, Chad's interim defence minister.
"We destroyed seven pockets of groupings of mercenaries. We hit them with our aircraft along the border, without any collateral damage," Younousmi said in a statement, using the term mercenary to describe the eastern Chadian rebels.
"We captured about 100 prisoners who will be shown within 48 hours," he added.
Chad and Sudan have long traded accusations of backing each others' rebels, which have waged simmering rebellions in the remote shared border region.
Most of the fighting has not spread from Sudan's Western Darfur region and Chad's east. But last year rebel offensives reached both countries' capitals before being beaten back.
Younousmi said the operation, which had involved ground forces, had reached as far as 40 km into Sudan but stressed the target had been neither Sudan's government nor its people and there had been no collateral damage.
"Chad will no longer accept groups of mercenaries reorganising and rearming to attack it, wherever they are. However far it takes us, we will go by land, air and sea to destroy the mercenary bases," he said.
(Writing by David Lewis; editing by Mark John)