By Kenny Katombe and Chrispin Mvano
KINSHASA (Reuters) - A U.N. peacekeeper was killed and another injured during a third day of fighting between government forces and rebels in eastern Congo on Sunday, as the army pressed toward the rebel stronghold of Rutshuru.
The U.N. mission in Congo (MONUSCO) said the Tanzanian peacekeeper was killed during fighting with M23 rebels in the town of Kiwanja, north of the regional capital Goma, the largest city in eastern Congo.
"The soldier died while protecting the people of Kiwanja," Martin Kobler, the head of MONUSCO, said in a statement. The previous round of clashes between the army and rebels in late August killed at least two Tanzanian peacekeepers.
Following two months of relative calm in the region, fighting flared up on Friday after peace talks in Uganda broke down when M23 pressed for a full amnesty for its leaders. Each side blamed the other for starting the fighting.
President Joseph Kabila, who last week threatened a return to military action, said an unconditional amnesty not an option.
A Congolese army officer on the front line said the army took Kiwanja and Kalingera from M23 on Sunday, a day after wresting the strategic town of Kibumba near the Rwandan border from the insurgents.
Fighting was continuing at Kiguri, 25 km (15 miles) north of Goma, he said.
The army had also opened a second front to the north of M23 positions and was moving southward to Rutshuru, officers said.
"We are consolidating the zones we have conquered," army spokesman Colonel Olivier Hamuli told Reuters near the front line. "Very soon we will take Rutshuru. Those who disarm we will accept, the others we will pursue."
M23 said in a statement on Sunday it had withdrawn its troops from Kiwanja, accusing the army of sending in fighters in civilian clothing to try to draw U.N. troops into the conflict.
M23 threatened to withdraw its delegation from the stalled peace talks in Kampala unless there was an immediate end to hostilities. It said it would then launch a large-scale counter-offensive.
Congo's army, supported by a new U.N. intervention brigade, scored its first victories against the rebel movement, which has been fighting for nearly two years, in late August, forcing the rebels away from Goma.
The U.N. brigade has a tough new mandate to eliminate armed groups in the eastern provinces, though it has not been involved in the past three days of fighting.
The support of the brigade and the weakening of the rebels has fuelled belief that Congo's army - notoriously disorganized, undisciplined and under-supplied - could defeat M23.
Army sources told Reuters reporters in Goma that M23 had been weakened by desertions, with some 40 rebels taking advantage of a corridor created by the government troops to allow then to flee rebel lines.
M23 began in early 2012 as a mutiny by soldiers demanding the government implement the terms of a 2009 peace deal signed with a previous Rwanda-backed rebel group, many of whose members had been integrated into the army.
U.N. investigators and the Congolese government have accused Rwanda of supporting M23, charges Rwanda has repeatedly denied.
Army spokesman Hamuli said some M23 fighters had fled towards the Rwandan border in the face of the army advance.
"There are small pockets of M23 resistance in the hills near Rwanda," he said. "We think Rwanda has to prove its good faith and oblige M23 to disarm, or disarm them itself."
He refused to discuss the possibility of a return to peace talks in Kampala. "We are soldiers," he said. "We will continue to do our jobs as soldiers."
(Reporting by Pete Jones; Writing by Daniel Flynn; Editing by Alison Williams)