Fighting across the largest city in eastern Democratic Republic of Congo and "is still very much ongoing ... it's not over yet," senior U.N. official in Congo, Bruno Lemarquis, said on Monday after Rwandan-backed M23 rebels claimed to have control of Goma.

Goma is on the brink of falling after M23 rebels and Rwandan troops entered the eastern Congolese regional capital. The border between DRC and Rwanda was closed, and Kenyan President William Ruto convened an extraordinary East African Community summit amidst escalating uncertainty.

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.

The Democratic Republic of Congo’s government says the Rwanda-backed rebels’ advance constitutes 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.

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