Rwandan-backed M23 rebels in Democratic Republic of Congo were moving south on Wednesday towards Bukavu, the capital of South Kivu province, in what appeared to be an attempt to expand their area of control in the country's east after capturing the city of Goma.

Democratic Republic of Congo President Felix Tshisekedi has insisted that his troops are mounting a "vigorous" response to Rwanda-backed fighters advancing in the country’s perennially troubled east,

U.S. Secretary of State Marco Rubio called for a urgent cease-fire in the conflict in eastern Democratic Republic of Congo saying Washington was "deeply troubled" by a recent escalation in the fighting.

The rebels, which Rwanda denies supporting, have long been funded at least in part by the illicit mineral trade.

M23 rebels in the Democratic Republic of Congo have seized Goma and are advancing towards Bukavu, amplifying tensions in the region. The conflict, fueled by resource control, has overwhelmed local hospitals and forced Romanian mercenaries to withdraw.

Rwandan backed rebels have entered the city of Goma, a key city in neighboring Democratic Republic of Congo. Could the mineral rich region be in danger of tipping into all out regional conflict?

United Nations chief Antonio Guterres on Sunday urged Rwanda to withdraw its forces from the eastern Democratic Republic of Congo where fierce fighting raged as Kigali-backed fighters closed in on the major city of Goma.

A lightning advance in Congo's mineral-rich eastern borderlands is set to boost the M23 rebellion's illegal mining revenues, with analysts predicting a further surge in illicit trade in minerals including coltan and gold through neighbouring Rwanda.

Democratic Republic of Congo President Felix Tshisekedi said Wednesday that the international community's failure to respond to the worsening security crisis in the country's east was "an affront",

M23 plans to govern the city of Goma - a key gateway to rich mining areas that produce valuable resources like gold, tin, and coltan - giving the armed group access to trade routes and economic power

Democratic Republic of Congo President Felix Tshisekedi, speaking publicly for the first time since Rwandan-backed rebels seized the eastern city of Goma, said his government was preparing a response and warned of “unpredictable consequences” for the region.