Rwanda-backed M23 rebels have captured the strategic border city of Uvira in South Kivu, deepening the crisis in eastern Democratic Republic of Congo (DRC) and defying a U.S.-mediated peace accord signed just days earlier in Washington.

M23 spokesman Lawrence Kanyuka declared on X: “Uvira is now under full control of AFC/M23. We call on fleeing residents to return home safely.” Local sources confirmed Congolese army units abandoned positions overnight amid heavy clashes, with gunfire echoing across the city.

The fall of Uvira — a commercial hub linking DRC to Burundi and Tanzania on Lake Tanganyika — comes only nine days after M23 seized Bukavu’s provincial capital. It marks the group’s deepest southern advance since the offensive began in late 2024. UN partners report more than 200,000 newly displaced in South Kivu since December 2, with at least 70 killed.

The advance directly undermines last week’s Washington peace deal, which required Rwanda to halt support for armed groups and Kinshasa to neutralize Hutu militias like the FDLR. Neither side has formally commented, though President Félix Tshisekedi accused Kigali of violations in a parliamentary address earlier this week.

Meanwhile, a humanitarian catastrophe is unfolding across the border. The UNHCR recorded 40,000 Congolese refugees crossing into Burundi between December 5–11. Transit sites in Kansega, Cishemere, and Gatumba are overwhelmed, lacking water, latrines, and shelter. UNHCR’s Brigitte Mukanga-Engo warned of “desperate conditions” and announced a new camp opening in Bweru.

Refugees described harrowing escapes under bombardment. “We lost everything. My brother was killed by a bomb,” said Fidèle Edimbe, 32, from Uvira. Burundi, already hosting 71,000 Congolese refugees, is struggling to cope.

According to OCHA, the M23 offensive has displaced over 1.2 million people in eastern DRC since January 2025, with aid agencies warning of famine-like conditions in besieged areas.

The capture of Uvira exposes the fragility of peace efforts in the Great Lakes region, raising urgent questions about the viability of international mediation and the capacity of regional states to contain the spiraling conflict.