Rwanda-backed rebels entered the outskirts of eastern Congo’s largest city, Goma, on Sunday, causing what the United Nations called “mass panic” among its 2 million people and leading Congo’s government to call it a “declaration of war.

Rebels in Democratic Republic of Congo are closing in on a key city in the mineral-rich region aided by neighboring Rwanda’s army, the head of a peacekeeping mission told United Nations Security Council members during an emergency meeting on Sunday.

Rwandan-backed fighters closed in on eastern Congo's largest city of Goma on Sunday, forcing thousands of civilians to flee and grounding flights from the local airport as government forces battled to stop the rebels seizing the city.