Nearly 3,000 people have been killed in the city of Goma in the eastern Democratic Republic of Congo, according to the United Nations, after it was captured by rebels following days of fierce fighting with the Congolese army.

Officials and residents say Rwanda-backed rebels have gained ground in eastern Congo despite the unilateral ceasefire they declared earlier this week, taking control of a town 100 kilometers (60 miles) from the provincial capital of Bukavu.

The cost of some essential food items has more than doubled in Goma, the main city in eastern Democratic Republic of the Congo that was captured by M23 rebels last week, according to locals and an NGO.

When M23 rebels swept into the Congolese city of Goma this week, world powers urged them to immediately withdraw. Instead, the Rwanda-backed insurgents are intent on showing they can restore order and govern.

The fragile ceasefire in eastern DR Congo is on the verge of collapse as Rwandan-backed M23 rebels reportedly seize control of Nyabibwe town in South Kivu province. The mining town, a key commercial hub between Goma and Bukavu,