At least 773 people have been killed in Goma and surrounding areas in eastern Democratic Republic of the Congo (DRC) following an offensive by the M23 rebel group, authorities reported Saturday. The rebels, reportedly backed by Rwandan forces, captured Goma in the most significant escalation of the region’s conflict in more than a decade.

Patrick Muyaya, the Congolese government spokesperson, warned that the death toll could be higher as the rebels allegedly instructed civilians to clear the streets, potentially concealing additional bodies. “There should be mass graves, and the Rwandans took care to evacuate theirs,” Muyaya said during a press briefing in Kinshasa.

M23 leader Corneille Nangaa has declared intentions to advance further into Congolese territory, vowing to push toward the capital, Kinshasa. In response, President Félix Tshisekedi has called for a national mobilization, promising to reclaim all occupied areas. “We will reconquer every inch of our territory,” Tshisekedi said.

The United Nations reports that more than 400,000 people were displaced in January 2025 alone due to renewed fighting. The humanitarian crisis has intensified as basic services in Goma, including water and electricity, have been cut off for several days. Residents returning to the city have been met with widespread destruction and bodies littering the streets, according to NBC News.

M23, one of more than 100 armed groups active in eastern DRC, is supported by an estimated 4,000 Rwandan troops, according to U.N. experts. The group’s advance southward has slowed in some areas due to counterattacks by the Congolese military, which has reclaimed a few villages. However, the military has suffered significant losses, with hundreds of soldiers killed and foreign mercenaries reportedly surrendering after the fall of Goma.

The conflict has also disrupted humanitarian operations across eastern DRC. Mercy Corps’ country director, Rose Tchwenko, said the violence has brought aid efforts to a halt, leaving communities stranded without access to essential supplies. “The escalation of violence toward Bukavu raises fears of even greater displacement,” she said, referring to the provincial capital of South Kivu, about 60 kilometers south of the rebels’ current position, according to Al Jazeera.

U.N. peacekeeping chief Jean-Pierre Lacroix noted that M23 forces, along with Rwandan troops, are advancing rapidly toward Bukavu, capturing key infrastructure, including airports, along the way. The capture of Bukavu would mark a significant strategic victory for the rebels, allowing them to reclaim territory lost since the end of the DRC’s two major wars between 1996 and 2003. Those conflicts claimed between 3 million and 5.5 million lives, mostly due to malnutrition and disease.