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 M23 rebel group has made significant territorial gains along the border with Rwanda in recent weeks, closing in on Goma, the provincial capital.

Rwandan backed rebels have entered the city of Goma, a key city in neighboring Democratic Republic of Congo. Could the mineral rich region be in danger of tipping into all out regional conflict?