France, Jan. 31 -- The Rwandan-backed armed group M23 moved south as it closed in on a key military airport in DR Congo on Friday, a day after pledging to take the capital Kinshasa and as international criticism mounted.

The group's capture of most of Goma, the capital of North Kivu province, earlier in the week was a dramatic escalation in a region that has seen decades of conflict involving multiple armed groups.

Rwanda says its primary interest is to eradicate fighters linked to the 1994 genocide but is accused of seeking to profit from the region's reserves of minerals used in global electronics.

The crisis has rattled the continent and international observers, with a southern African regional bloc holding an emergency summit in Zi...