Rwanda-backed rebels were quickly expanding their presence in eastern Congo after capturing Goma, the region's major city, the U.N. said Friday, also expressing concerns over executions it learned were carried out by the rebels following a major escalation of their yearslong rebellion.

Rwanda-backed rebels have captured eastern Congo’s strategic city of Goma, the hub of a region containing trillions of dollars in mineral wealth that remains largely untapped. It marks a sharp

Colleta Nzabonipa, 54, sits among other internally displaced people who fled from various camps following fighting between M23 rebels and the Armed Forces of the Democratic Republic of the Congo, in Goma,