Residents say Rwanda-backed rebels appear to be heading toward a third major city in eastern Congo. International pressure rose Tuesday over the M23’s expansion in the mineral-rich region that’s critical for global technology.

Boat traffic returned to eastern Democratic Republic of Congo's Lake Kivu on Tuesday as ports re-opened in two cities which have fallen to M23 rebels, a development the United Nations said could facilitate access to humanitarian aid after weeks of fighting and looting.

M23 rebels backed by Rwanda took the city of Goma in a bloody battle. This weekend, the group entered the gold-trading center of Bukavu in eastern Congo after government soldiers fled.