Rwanda-backed rebels appeared to be heading toward a third major city in eastern Congo, frightened residents said Tuesday, as international pressure rose over the M23's expansion in the mineral-rich region that's critical for global technology.

M23 rebels in the Democratic Republic of Congo have captured the eastern city of Bukavu with the backing of Rwandan forces, the second major city in the mineral-rich Kivu region to fall in three weeks.

Rwanda-backed rebels have reached the center of east Congo’s second-largest city, Bukavu, and taken control of the South Kivu province administrative office