Rwanda-backed rebels who have captured eastern Congo’s largest city say they plan to take their rebellion to the capital and seek to gain political power.

Rwandan-backed M23 rebels have seized control of a mining town in eastern Democratic Republic of Congo's South Kivu province, eight sources said on Wednesday, in an apparent violation of a unilateral ceasefire they declared this week.

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.