M23 rebels claim they now control the Congolese city of Goma—an act Congo's government described as a 'declaration of war.'

Rwanda-backed rebels claimed they captured eastern Congo’s largest city, Goma, early Monday, as the United Nations described a mass panic among its 2 million people and Congo’s government said the rebel advance was a “declaration of war.

The U.N. said the rebels were supported by at least some regular Rwandan troops, in the worst escalation of a long-running conflict for more than a decade.