RUTSHURU, Democratic Republic of Congo Congo's U.N.-backed army closed in on some of the last pockets of territory held by M23 rebels on Wednesday, a local commander and a United Nations official said.
Rebel officials, who have retreated in the past only to resume fighting, were not immediately available for comment, though their Twitter account said there were clashes 20 km (12.4 miles) from Bunagana, near the border with Uganda and Rwanda.
Democratic Republic of Congo's army has pushed the rebels back several times over the last week, prompting the French ambassador to the United Nations to declare on Monday that M23 was "militarily finished".
Government forces were moving towards Bunagana and nearby Mbuzi and Runyoni with the aim of stamping out the 20-month rebellion, a Congolese commander said, asking not to be named.
"We are progressing. We will not stop. We must finish with M23 once and for all," he added.
A U.N. official in the eastern border town of Goma told Reuters: "As far as we know the situation is entirely under the control of the army. From the information we have they are not yet in Bunagana but they are approaching."
The U.N. peacekeeping mission in Congo, known as MONUSCO, said on its Twitter page on Wednesday that "several dozen" M23 rebels had turned themselves in.
A spokesman for Uganda's army denied a local media report that M23 leader Bertrand Bisimwa had been arrested after crossing into Uganda. Bisimwa was travelling to Kampala, where peace talks have been taking place, to speak to mediators, the spokesman said.
Congo's east has been plagued by cycles of rebellion and the United States has called for a return to talks, warning of further violence if no diplomatic solution is found.