Residents in Goma, the largest city in the east of the Democratic Republic of the Congo (DRC), were fleeing on Monday after the Rwanda-backed M23 armed group claimed to have captured the regional hub from Congolese forces as fighting escalated despite calls from the United Nations Security Council for the rebels to withdraw.

Gunshots rang out across Goma overnight before dozens of rebels in military uniform early Monday morning marched into the capital of North Kivu province, which sits on the border with Rwanda in the volatile region rich in minerals that are critical to much of the world’s technology.

The Congolese government confirmed the presence of M23 rebels in Goma, 1,500km (930 miles) east of the capital Kinshasa, but stopped short of saying they were in control of the city.

In a statement on X, government spokesman Patrick Muyaya asked Goma residents to stay at home and also urged Congolese nationals around the world to mobilise in support of the country. “No centimetre will be given up!!!” Muyaya wrote.

The March 23 Movement (M23) is one of about 100 armed groups vying for a foothold in the mineral-rich region in the decades-long conflict. The rebels temporarily took over Goma in 2012, before they were forced to pull out under international pressure, and resurfaced in late 2021, with increasing support from Rwanda, according to Congo’s government and UN experts. Rwanda has denied such support.

Rwanda’s Ministry of Foreign Affairs accused DRC of failing to enter a dialogue with M23, which it described as a “Congolese rebel group fighting to protect their community”.

That failure, it said, has prolonged the fighting that continues to present “a serious threat to Rwanda’s security and territorial integrity, and necessitates Rwanda’s sustained defensive posture”.