A rebel group that claimed to have captured the city of Goma in the eastern Democratic Republic of Congo last week has called for an immediate humanitarian ceasefire, after fighting with the Congolese military has left hundreds of people dead.

There has been fierce fighting as Rwanda-backed M23 rebels advance towards the second-largest city in eastern Democratic Republic of Congo, marking a further escalation in the region's conflict. M23 fighters have been moving south, towards Bukavu, the capital of South Kivu, after capturing the largest city in the region, Goma.

The group called the Congo River Alliance also includes the Rwanda- backed M23 rebels, who were reported to be gaining territory in other eastern parts of the country while advancing on South Kivu's provincial capital,

Congo government forces were nowhere to be seen as the M23 rebels in Democratic Republic of Congo were moving south on Wednesday towards Bukavu, the capital of South Kivu province

Over 2,000 bodies require burial in Goma after Rwanda-backed M23 rebels took over the Democratic of Congo city last week, inflaming a decade-old conflict and humanitarian crisis, Congo's communications minister Patrick Muyaya said late on Monday.

M23 rebels in the Democratic Republic of Congo said they would begin a unilateral ceasefire on Tuesday as the Group of Seven nations demanded that the Rwanda-backed militia halt an offensive that has shaken the eastern part of the country.