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.

Rebels appear to be edging closer to taking control of the key city of Goma in the east of the Democratic Republic of Congo following reports that they had captured its airport. The Congolese government has insisted that it is still in charge as fighting in parts of the city continues.