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Gunmen have seized at least two villages overnight in the eastern Democratic Republic of the Congo (DRC) near the border with Uganda and Rwanda, a local official and an activist group said.
On Monday, Lieutenant-Colonel Muhindo Luanzo, assistant to the administrator of Rutshuru Territory, blamed the attack on fighters from M23, a rebel group that seized large swaths of territory in 2012 and 2013.
The two villages, Tshanzu and Runyoni, were the last redoubts of M23 before they were chased by Congolese and United Nations forces into Uganda and Rwanda in 2013.
Since then, there have been regional efforts to demobilise the fighters, but the group has complained about the slow implementation of a peace accord and some have returned to the DRC.
It was not immediately possible to confirm the identity of the armed men who took over the two villages.
M23 officials and spokespeople for the DRC’s army and government did not immediately respond to requests for comment.
Luanzo said the gunmen stormed Tshanzu and Runyoni simultaneously late on Sunday night.
“Now our troops are conducting counterattack operations because, during the night, they identified the enemy coming from Rwanda,” Luanzo told Reuters news agency by telephone.
UN investigators have accused Rwanda and Uganda, which intervened militarily in the DRC during two regional wars two decades ago, of supporting M23. The two countries deny this.
A local activist group reported clashes with light and heavy weapons on Sunday night that forced people out of their homes and across the border at Bunagana into Uganda.
“Uganda is experiencing an influx of refugees from DR Congo,” said Irene Nakasiita from Uganda’s Red Cross Society.
Al Jazeera’s Malcolm Webb, reporting from Nairobi in neighbouring Kenya, said some of the people fleeing claim to have recognised some of the commanders of the M23 group – which has been accused of rights abuses.
“Hundreds of people have crossed through the town of Bunagana,” Webb said.
On Sunday evening, the United States issued a security alert, warning of a potential attack on the provincial capital of Goma, which is about 50km (31 miles) to the southwest of the two villages, and advising its personnel to shelter in place.
Meanwhile, all major streets in Goma were later filled with soldiers, a Reuters journalist said.