Clashes last week in the eastern Congolese city of Goma, which saw the M23 group and Rwandan forces seize control, have left at least 2,900 people dead, a United Nations official said on Wednesday.
"So far, 2,000 bodies have been collected from the Goma streets in recent days, and 900 bodies remain in the morgues of the Goma hospitals," Vivian van de Perre, deputy chief of the UN peacekeeping mission in the Democratic Republic of Congo (MONUSCO), told a video news conference.
On Thursday, Rwandan-backed M23 called its first public meeting since seizing the Congolese city of Goma after deadly clashes, as its fighters advanced towards another regional capital.
After capturing Goma, the main city in North Kivu province, last week, the M23 and Rwandan troops launched a new offensive on Wednesday in a neighbouring province.
Breaking a ceasefire it had declared unilaterally, the fighters seized the South Kivu mining town of Nyabibwe, about 100 kilometres from the regional capital Bukavu.
The M23 anti-governmental group had said in declaring the humanitarian ceasefire that it had "no intention of taking control of Bukavu or other localities."
Humanitarian and local sources said on Thursday that Congolese forces were bracing for an assault in the town of Kavumu, which hosts the province's airport and lies about 30km from Bukavu.
Equipment and troops are being evacuated to avoid being captured by the advancing M23 and its Rwandan allies, the sources said.
The fall of Kavumu, the last barrier before Bukavu, would be another stinging setback for the army and government of the Democratic Republic of Congo.
In more than three years of fighting, the M23's lightning offensive against Goma was a major escalation in the mineral-rich region, scarred by relentless conflict involving dozens of armed groups over three decades.
Residents of the city of one million people have been told to attend the M23's public meeting in the stadium on Thursday.
Men using loudspeakers went through the streets a day earlier instructing the population that their presence was mandatory, an AFP journalist saw. Businesses are to remain shuttered on Thursday at M23's request.
