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.

Rwanda-backed rebels have captured eastern Congo’s largest city, Goma, as the United Nations reported “mass panic” with the government dubbing the insurgency a “declaration of war.” The city’s capture came following a 48-hour deadline imposed by the M23 rebel group for the Congolese army to surrender their weapons.

Gunfire rang out early on Monday across parts of Goma, the largest city in eastern Congo, hours after Rwanda-backed rebels said they had seized the city despite the United Nations Security Council's calling for an end to the offensive.