Democratic Republic of Congo President Felix Tshisekedi has vowed “a vigorous and coordinated response” against a rebel alliance that has besieged swaths of the nation’s mineral-rich east and forced hundreds of local troops and foreign mercenaries to surrender.

The rebel leader whose fighters have captured Goma, the biggest city in eastern Democratic Republic of Congo, has vowed to continue their offensive all the way to the capital, Kinshasa. Corneille Nangaa, who heads an alliance of rebel groups that includes the M23, said their ultimate aim was to topple President Félix Tshisekedi's government.

Rwanda-backed rebels claimed on Monday they captured eastern Congo’s strategic city of Goma, the hub of a region containing trillions of dollars in mineral wealth that remains largely untapped.