Displaced people who fled clashes between the Congolese army and M23 rebels try to timidly return to their homes in Kibumba, a few kilometres from the city of Goma in eastern Democratic Republic of Congo, on June 1, 2022. (GUERCHOM NDEBO / AFP)

GOMA, Democratic Republic of Congo - M23 rebels in the Democratic Republic of Congo have seized the eastern town of Bunagana on the border with Uganda, local activists said on Monday, in a setback for Congolese forces who had said a day earlier they had the insurgents on the run.

Bunagana was an M23 stronghold during a 2012 insurrection that briefly overran the major city of Goma before Congolese and UN forces chased the rebels into neighboring Rwanda and Uganda the following year.

Bunagana was an M23 stronghold during a 2012 insurrection that briefly overran the major city of Goma before Congolese and UN forces chased the rebels into neighboring Rwanda and Uganda the following year

The town is around 55 km (35 miles) northeast of Goma and one of the main crossings into Uganda.

"We are already under M23 control," Jean-Baptise Twizere, the president of a local civil society group, told Reuters on Monday from Bunagana.

"Congolese soldiers who found themselves encircled by enemies in Bunagana could not do anything and since 11 pm (on Sunday), they have left the city," he said.

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Edgard Mateso, the vice president of an advocacy group in North Kivu province, confirmed the M23 takeover.

General Sylvain Ekenge, the spokesman for North Kivu's military government, said he did not yet have any information and was on his way into the field.

The governor's office said on Sunday Congolese forces had "routed" the M23 following early-morning attacks near Bunagana, killing several fighters.

Congolese authorities on Sunday accused Rwandan soldiers and artillery of supporting the M23's attack on Bunagana. Rwanda has repeatedly denied backing the rebels' latest offensive, which began last month.

The violence in Bunagana pushed over 25,000 people to flee the area, with thousands escaping to neighboring Uganda, the United Nations said on Sunday.

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Batu Banyeho,77, returned home to Kibumba after spending a few days in the displaced persons camp in Munigi following the clashes between the Congolese army and the M23 rebels in Kibumba, a few kilometers from the city of Goma, in the eastern part of the Democratic Republic of Congo, on June 1, 2022. (GUERCHOM NDEBO / AFP)